I'm not sure exactly when it happened, but Google has quietly added IMAP support to Gmail. That's very interesting, though I'm pretty sure it won't help anyone (like me) hoping to access their server-based Labels views (Google's implementation of virtual folders using live database-like queries). I will test this to find out.

Gmail: How do I enable IMAP?
Gmail: Configure IMAP for your iPhone

What's really needed, I'm guessing, is a Gmail version of the Outlook Connector, where these Labels views will just show up as "folders" in the Outlook tree. Still, better than POP3.

Thanks Martin!