The new version of this cloud-based application should be faster in opening e-mails, quicker navigation and searching through your Gmail account.
New Gmail app brings several much wanted features such as selecting more than one message [you can Archive, Delete, Mark as read/Unread or Spam, Bacon and Sausage], floating tool bar [moves as you move/scroll through messages], and the search button is now moved on the top of the page for easier usage. This version brings improved caching as well - when the internet connection is bad/nonexistent you can still open recently read messages and write new ones and when the connection is restored, the message will be sent.
Probably the best e-mail app for your iPhone... for its own free e-mail service, naturally.
These new features are interesting but the real importance is that Google has shown how significant and powerful mobile web browsers have become especially in running web based applications.
The app requires iPhone/iPod Touch OS 2.2.1 or above, and as always, if you have some feedback or ideas you can send it here.