Wow, it's been a while, hasn't it?
Well, the website seems to have stopped with the monthly character updates--the last two wallpapers have been calendars with new renders of Sonic and Tails.
There HAVE been some other updates of note, however, including the JPN page for Sonic Rush Adventure, a papercraft of the original Tornado
for Sonic's 16th birthday, and most recently, three PDF files
that give the user some interesting Sonic-themed staionery.