Update Market Application to Google Play Market Application
Try clearing the data for the Market and rebooting the phone.  Then log in to the Market, wait a minute, then back out and continue using your phone with the internet connection active.  Hopefully the Market should update itself within a few minutes.

Or, you can just download and install the .apk.  I rely on Android Police for the latest version; they've posted 3.9.16 here.