It appears that a save game issue has developed with Arkham City/Windows Live.
My save games have disappeared from the in game menus. Suck.
Word is there is going to be a patch to fix, but until then. . . . Suck
Intel i7 950 @ 3.9 GHz
MSI 560 Ti Twin Frozr x2 SLI @ 950 mhz
6 GB of Corsair memory (timings unknown atm)
H50 CPU cooler
3dMark11 P7800 at stock speed, P8643