The graphics aren't being remade for Sonic Adventure 2, but both games are getting the High Definition, Wide-Screen release treatment this October 2 & 5. For $10 (800 Microsoft Points) each, the NiGHTS into dreams... with Christmas Nights bundle and Sonic Adventure 2 are going on sale as part of the "SEGA Heritage" line. The "Battle" portion of Sonic Adventure 2 (added for the GameCube re-release) will be sold separately for an additional $3.00 / 240 Microsoft Points.

Both of these games are great, and NiGHTS is looking impressively colorful with its updated visuals. The days are October 2 for PSN, October 5 for XBLA. Both games have had Achievements or Trophies added. No PC Windows release has been announced.

Jet Set Radio (Jet Grind Radio), similarly updated, is releasing around September 19 on PSN/XBLA/PC.

Source (with screenshots): http://blogs.sega.com/2012/09/17/nig...le-in-october/