Gmail for mobile version 2.0 is for J2ME-supported and BlackBerry phones (not windows based!)

They have made it faster, more reliable, and reduced bottle-necks in the coding. 

 Here are some key features:

• Overall performance improvement: You should experience significant raw speed improvement, smoother scrolling, and no freezing.
• Multiple accounts management: If you have both a Gmail and Google Apps email account, you can easily switch between them quickly. You will no longer have to use two different mobile apps to access personal and work emails.
• Multiple mobile email drafts: You can save multiple email drafts in your mobile phone, so that you can pick and choose what you would like to send later.
• Powerful shortcut keys: If you have a QWERTY phone, you can use shortcut keys. Hit ‘z’ to undo, ‘k’ to go to a newer conversation, and ‘j’ to go to an older conversation. See Menu/Help in the app for more shortcuts.
• Basic offline support: Can’t get a signal? Not a problem. You can compose and read your most recent emails even when there is no signal. Also, any outgoing messages will be saved in the outbox on your phone and sent automatically when you’re back in coverage.

 Go to m.google.com/mail in your mobile browser to download the new Gmail for mobile for your phone.

Or goto http://www.google.com/mobile/default/mail/index.html for further information.