People have been waiting for a Gmail app for the iPhone for a long time. Heck, even the Facebook iPad app got here sooner. Google finally launched the app yesterday for all the i-devices but when people fired it up they got an error message saying "no valid 'aps-environment entitlement string found for application." Whoops. Google then pulled the app again to fix it. It makes you wonder if they, you know, tested the dang thing.
Bugs aside, the Gmail iOS app still needs more work. Scrolling is sometimes laggy, button taps can be slow to respond, and there's no support for multiple inboxes. It's not clear whether Google will add some extra polish to the app before it's sent off again for approval.
Personally, I don't see what the big deal is. I can get to Gmail from my iPhone's email app or from the browser on my iPhone (just as I do on my computer) so I've never even thought about wanting another app I'd have to pull up just for one of my email accounts.