This has been around for some time. I believe they're using technology from ITA, which was acquired by Google in 2010 [1]: http://matrix.itasoftware.com/
(It's also what most flight hackers use to search for tickets.)
It's now coming up because they're integrating it into the new version of Maps. If you search for a driving distance that's sufficiently far away, they will also suggest flights as an alternative.
One thing you have to be careful of is with connecting flights of differing airlines. Sometimes it will propose an itinerary that just isn't realistically possible to make because you won't be able to get to the other airline in time. I've only encountered this once or twice. Otherwise, I use it all the time, successfully booking many flights through it.
This is disappointing. With all the data they now have access to through the ITA purchase, this is still much worse than what I can achieve with ITA Matrix (http://matrix.itasoftware.com/).
Love what you've done with Hipmunk, it's a fantastic resource to use with flights originating in the US. Sadly it hasn't given me much joy with my European or African routings.
Flights from almost all airports Google flights doesn't even supprot some of the major international hubs, Tokyo, Singapore, Hong Kong all not available.
Realize that Google uses a lot of caching to make this fast; the prices are actually pretty stale. The more up to date the information the slower accessing it is. Generating flight itineraries and prices with near realtime availability (especially for today and tomorrow) is incredibly difficult to do. The less often you do it the faster the result can be. Since Google isn't a seller of seats they also avoid all the crap the DOT requires on disclosure and accuracy. I only wish it was possible to do real-time this fast.
Agreed, although I always thought the sticking point for SWA was paying commissions and not data access. For a sample search from BWI-SFO their price was only about $20 more expensive than the lowest fare ($520).
On the two occasions I have used it, Google flights was able to find me cheaper tickets than what Southwest offers. It is now my first stop, and then I double check Southwest to see if they can beat what Google has shown.
The first impression I got from this was an interesting combination of creepy and incompetent.
The creepy part: The site gave 5 suggestions for places I might want to fly to. 3/5 were cities I've traveled to multiple times in the last few years. And while I might accept e.g. London as a default suggestion for anyone in Europe, something like Helsinki is a lot harder to justify.
The incompetent part: Google knows damn well I live in Zurich. They have Google+ profile information, they have my Android information, they have ip geolocation (which definitely gets my ISP right). So why is the suggested starting airport 150 km away, in another country? Ridiculous.
I used to work a few rooms away from the guys doing Google's IP geolocation database. I am pretty sure that this city + ISP has good coverage and is well tested :-) Also, all other location-dependent Google services get it right.
As far as I can tell, Flights doesn't "officially" support flights from Switzerland yet. If you try to select ZRH as your only departure airport, you'll get an error message stating as much.
If you were recommended flying from MLH (aka BSL), I'd wager it's just the closest (active) airport to your geolocation. If you were suggested STR, your geolocation may be off by a bit.
To get some results for flights out of ZRH, select MLH as your departure, then, on the map, click the marker at MLH. A list of close airports (BSL, BRN) will pop up. Click "more airpots" and add ZRH to your selection. It then somewhat works. Take note of the list of unsupported airlines at the bottom of the map.
Any info on how does it stack up against skyscanner / esky ?
edit: after a few minutes i can say that while the UI is 100x better than the aforementioned competiton, the flights my usual route i take few times a year (LDN - KRK) only display the price for the most expensive companies, which sort of defeats the point of using a crawler/search engine for this. hopefully they will add easyjet/ryanair/etc soon.
I've experienced it myself searching on United.com. But yes, sticking with a single airline's usually a good idea — there are benefits towards acquiring elite status on a single airline's frequent flyer program (even when we're talking about airline alliances).
I usually use ITA Matrix > Expedia (which uses the engine, I think) > Orbitz (if it has more segments than Expedia can handle — this also uses ITA's engine).
For low-cost/budget flights around Southeast Asia, I just use Skyscanner.
$507 vs $528, and both have Pegasus where Momondo shows the cheapest Pegasus at $507 and Hipmunk at $553
and a self-quote from an email conversation I had in december about flight search engines: "Just to picture an example,
random query 30dec-05jan Warsaw-Istanbul. Hipmunk cheapest: 407usd (turkish). Momondo cheapest: 299usd (aerosvit). that's over 1/3 more."
"our goal will be to refer people quickly to a site where they can actually purchase flights, and that we have no plans to sell flights ourselves."
By the look of it, this indeed follows the guideline they set. Google has always had a strong dislike of aggregators, and this certainly could easily be a big hit to sites like that.
That said, while it is a slick interface, I know quite a few people who are going to be quite unhappy about this being released.
Wow, type in a place as a destination that doesn't have an airport (like Flagstaff, United States) and it will give you a map of the area, showing the lowest price for all the surrounding places.
I had intended to fly into Pheonix and rent a car to drive to Flagstaff, now I can clearly see where it's cheaper to fly into.
I'm the OP on reddit (posted this morning), note that there are a couple of other sites that do the same, and some which seem to have a better choice or airlines and prices.
I put a comment together with all the suggested sites:
This gives me an urge to be spontaneous for a weekend. I don't always want to know where I'm going until a few days before it; and, knowing where there are airports and which ones have non-stop flights at a moment's inspection is actually quite a cool and convenient thing!
Our friends have a concept called an Orblitz. You got to orbitz.com on Wednesday and search for the cheapest tickets out of the state to anywhere. Take a backpack for the weekend and no hotels book - figure it out there.
Has been a blast every time. I actually used the concept at a Noisebridge party once:
Is there a reason why they don't include something similar to Bing Flights' Price Predictor? I haven't actually booked a flight since they released that, but it seems like a nifty/useful piece of tech that Google would want an answer to.
Hmm, Google is missing the flexible dates and calendar view, while http://matrix.itasoftware.com/ is missing EasyJet and presumably other low-cost airlines.
http://rense.com/general96/shockingplanerad.html Who wants to fly when all that radiation is up there from Fukushima? Or is this rense guy way off the mark about this radiation you get when you fly?
I'm surprised at your result - Google Flights was effectively instant on the routes I tried, while on those same routes dohop.com had a progress bar that took over ten seconds to complete.
(It's also what most flight hackers use to search for tickets.)
[1] http://www.google.com/press/ita/