I'm still looking for a great alternative to Gmail/Google apps for my business email. Something that supports IMAP and has a reasonable webmail front end. Fastmail is the closest thing i've found but this could be a perfectly fine startup which probably simply isn't sexy enough for anything to actually go and do.

Gmail's IMAP implementation is really buggy. No distinction between tags and folders, non sorting done at the server level, etc. Frustrated, I also moved to fastmail two years ago; it is slightly expensive, but is standard's compliant and works flawlessly.

I should have maybe clarified that i too have moved to Fastmail (about a year ago) and am a happy customer. But both the price and the UI leave a lot of room for improvement, i.e. competitors.

And yes moving mail out of Gmail was a pain because of the weird IMAP structure they use.

I always use a local IMAP client (alpine), so am not really bothered by fastmail's rather basic UI.

I thought gmail didn't have folders; how is it supposed to distinguish the two?

IMAP has tags (rather keywords), that you can assign to multiple posts. Just because you assign a keyword to an email, doesn't mean that it should be moved to a new folder. Gmail does that, and therefore breaks IMAP.