I hated Gmail before I ever used it. Now I've been using it for about 5 months now and I've learned to complete despise it.
We use Google Apps here at REAL. I've heard when we managed our own server the e-mail system was a hassle, so letting Google handle it for us was not a bad idea. Now, we have a hosting service run our server for us, and e-mail is a breeze... for the mailing lists. All our @realsoftware.com addresses still go to Gmail.
And I really hate Gmail. I don't use the web interface, because I find it completely unusable. It wasn't so bad originally. The biggest problem was when using a desktop client, Gmail will not deliver messages with the same "from" and "to" addresses to you. They'll appear in your web inbox, but on the desktop, they hide it from you just to piss you off. I got a number of e-mails about that one, and I don't like responding with "sorry, it's out of my hands."
But now my biggest issue is Gmail keeps flagging legitimate messages as spam. Every topic notification I get from our forums keeps going to my spam box, and many of my status e-mails are too. This is really, really getting on my nerves and it's affecting the way I do my job. Well, kind of, I've added some contacts to the awful web interface, but I shouldn't have to.
I can't even turn off my spam filter and let Mail.app handle it. Worse still, since we have a Google Apps account, obviously all e-mails to realsoftware.com are part of Gmail - shouldn't it be smart enough to NOT flag inter-office emails as spam? I'm also getting complaints about Gmail's conversations making it difficult to keep track of conversations - I love the irony there. Gmail doesn't care about the "In-Reply-To" header and instead, groups conversations by subject. But since a lot of e-mails go out of customer service with the same subject to different people... you should be able to figure out where I'm going with this.
I'm tempted to work some of my trademark magic and find a way to have my address go to our server and let everybody else stay with Gmail. That way I can not worry about losing my mind and tossing myself our a window!
Please Google, stop trying to outsmart us. You suck at it.