Sync multiple gmail contacts with Lion Address Book

I have an iPhone 4. I love it. Google has a sync service for iPhone which will do #1 and #2. Your desire #3 is easily done through the browser. There's a built-in google maps app to fulfill your wish #4.

So, the iPhone can do what you want.

That said, it sounds like you want an Android.

EDIT, since you asked about hardware

After over 2 years of use, most of it without a case, except for a few minor scratches my iPhone 3G is fine. The only thing even close to degradation is a barely noticeable "stickiness" to the front main button.

My new iPhone 4 seems just as solidly built. I can't imagine these things falling apart without some sort of abuse.

Keyboard shortcuts: Mail has it's own keyboard shortcuts, which you may have to learn.

Alternate email addresses/multiple accounts: works fine. Don't know about plus-addresses.

Priority inbox: this is not supported. Labels work, as does flagging. Public calendars work in iCal.

Syncing is very easy to set up - via IMAP in Mail, and in Preferences in iCal. In Lion it's even simpler.

Yes, you add each account separately in mail. You can still visit them in any browser or device.