I don't know if you've used Opera, but it's by far the geekiest/most customizable browser, IMO. Total remapping of all shortcuts, ability to reconstruct the interface however you like from primitive controls, built in support for content (ad) blocking and mouse gestures, user script (Greasemonkey, sorta) support also built in, etc. I've never used Fastmail, but as you describe it, they couldn't have picked a better browser to sell to.
I do use Opera as my primary browser since I've gotten used to it from the 5.x timeframe. And I do agree that they could not have chosen a better browser to sell to.
However, I'm wondering if it should have been sold at all, specifically to a company that makes browsers. Why not to a hosting company like Rackspace's acquisition of Mailtrust and perhaps more importantly, why sell at all if it was a pretty profitable entity.
Now this may be the founder's big exit and I sincerely congratulate them for it, however my concern lies about the consumer (me). I hope it all turns out for the best of everyone involved, but I do have my reservations till I actually see FM operating as well as, if not better, than the FM of old.
The founder hasn't been involved with the service for years. The people who actually ran the service are still running it, and will keep doing that as Opera employees.
Also: Opera doesn't just make browsers. Opera also makes all sorts of services for both users and b2b customers. The browser just ties it all together.
