Gmail has introduced tabs to their inbox (the inbox is now divided into tabs). It seems to guess which tab messages should go to, but encourages people to make their own filters. So, it's exactly like labels?
Speaking of email, right now I'm looking for a way to "bounce" unwanted emails back to the sender. Hopefully this will make spammers think this address is invalid. I saw an antivirus suite with this feature before, but I can't remember which one.