But the name contains the string .exe! Clearly that means Windows is being emulated.
(Note to people that think this is true; install f-spot on Linux some time. It's a C# application, and ends in .exe. Even though it has nothing to do with Windows, except that Microsoft spec'd C# and Microsoft makes Windows...)
It's not correct to say that Picasa is emulated using wine. Instead, it's a native Linux app that has been ported using WineLib, which reimplements a lot of the Windows API, but compiled to Linux. Instead of replacing API calls with the Linux equivalents, there's just an additional layer that redirect calls or implements them.
(Note to people that think this is true; install f-spot on Linux some time. It's a C# application, and ends in .exe. Even though it has nothing to do with Windows, except that Microsoft spec'd C# and Microsoft makes Windows...)