It'd also be more compelling if this Facebook service was released yet and if anyone commenting on it actually had a chance to use it.

I don't know, I've always liked Apple Mail, simple and to the point. I do use MailTags though (http://www.indev.ca/MailTags.html)...

Before that, I used to use Foxmail, then Thunderbird and then Evolution and none of them have been as good as Apple Mail

I haven't used Apple Mail in at least 5 years. Last time I tried, it was adequate for one email account (which is probably what 80-90% of users have). Though it supported more, things always seemed to go weird after a while if you tried to use that. Maybe it's better now? When I last used it, it pretty much still seemed to be the NeXT Mail.app ca 1990.

I've used it for sometime now and it handles multiple accounts just fine. I run 3 IMAP accounts on it (served from Google Apps) and it handles all of them fine.

Its my favorite email client by far because of its simplicity in function and UI. I get some extended functionality from indev's products, in particular Mail Act-On for quickly sorting mail and Mail Tags. I'd love to see it with slightly tighter calendar integration but otherwise I love it.

http://www.indev.ca/

re: Apple Mail, it just depends on who you ask. If you prefer Gmail, then Facebook could have mimic'd Gmail UI instead. The point is that unifying the different transports doesn't solve a real user problem. It's not like people are having problems sending email or SMSes to each other today.