source --While I was more impressed by the T-Mobile G1 than I thought I'd be, the list of catches for Android and the phone are quickly piling up—some that might very well be dealbreakers. Topping the list, it's tightly integrated with your Google account—so tightly that you can only use one Google account with the phone. If you want to switch to another account, you have to do a whole factory reset. Update: T-Mobile has patched up some of them—the 1GB cap is gone, and they'll unlock the phone for you after 90 days.
Android and T-Mobile G1's Five Most Obnoxious Flaws
Y is it that all of these mobile OS developers do a half ass job and leave the rest for the independent developers