Ha...I've only recently downloaded this version, and then I started up software update on the phone, and guess what......Maps 3.1 available for download!!
(Confirmed when I started up Maps 3.03, and message pops up....new update available.)
So I'm currently downloading Maps 3.1 (5552kb) via the phone. I couldn't find this version to download via pc.
EDIT: I got excited for nothing.....the version 3.1 is actually v3.01.
For some reason it is showing up as v3.1 on the software update program