Well, I think it’s about time Gmail also makes up its own version of a fail whale (like on Twitter). Yes, you got it right! It’s down, yet again!
Looks like more of a Google Contacts issue because Gmail users started getting this message a while ago: Gmail is temporarily unable to access your Contacts. You may experience issues while this persists.
We all witnessed another major downtime at Gmail datacenters because of a DDoS attack a couple of days ago, and the interesting thing in this downtime was IMAP and POP users of Gmail could easily access their emails while others could not.
There are several alternate ways by which you can access Gmail when you sense something wrong is going on with it.