IanCP - 5:21 am on Feb 2, 2010 (gmt 0)
I similarly received the very same email.
"MailWasher" didn't report this as being from a "scam" email address site. Yes, I checked source code.
So why the hell would AdSense send you an email about last months payment?
Doesn't make sense at all.
Sadly, it immediately leads me to believe there is NO mechanism to report scammers to AdSense.
I don't believe for one second, AdSense is so stupid enough to send this totally meaningless email.
But someone "massaging or conditioning" you over a period of time may well do so.
You need to jump in on this right away. Yes I preserved my email and you're welcome to the source code.
For others, if it's legitimate or not:
Respond to this email until we "officially" know otherwise.