I've had an account for a while and it definitely has helped my Vim-foo, one of the few little cutesy services I've actually paid money for. It's somewhat relaxing and the fact that it's not some kind of monthly payment pulled me in. The database of shortcuts grows all the time as well. If you are considering trying it out I recommend it.
I was just thinking the exact opposite. I am really not convinced that the site can be maintained indefinitely for a $15 one-off payment per user. And when it inevitably closes down I will feel cheated out of the "lifetime" of service I paid my $15 for, whereas I would have been happy to pay $60 a year for it. ($5/month would also ring alarm bells for me, even though the total price would be the same.)
