The Gmail team is most definitely aware of this and a fix is in the works. At SXSW this year there was a panel with four or five Gmail team members and this came up — they said it's related to the size of your inbox, and that it has a lot of Googlers complaining internally too, since many of them have the oldest/large accounts. Also see http://techcrunch.com/2010/03/14/gmail-slow/ , though it has basically the same i…
Y'know, this article isn't about Gmail performance nearly as much as it is another article about Google's utter disdain for our quaint notions of customer service and transparency. Somebody who goes to a conference might get something like feedback and disseminate it to the masses - but that's it. Google is not interested in hearing about problems, and if they themselves are affected by a problem, well, boy howdy, th…
After a fairly intensive search, I found the reason in an obscure Google Groups posting[ http://groups.google.com/group/Google-Desktop_Something-Brok... ]. I experienced the bug six months after the issue was discussed there, and that was the only source of information I could find.
I don't know if Google has improved its support recently, but the obscure way in which information on the bug was disseminated certainly made me more wary of using Google products after that.