If it has the R360 core and can overclock to 9800XT speeds as it is now, yes. The only way to tell if it has the R360 core is to remove the heatsink, wipe the thermal paste or tape off, and read the specs on the gpu. MSI uses a reference designed PCB. If it used the same PCB as ATI or Sapphire, you can look at the component layout on the board and get a good idea if it is worth removing the heatsink to make sure. But since MSI uses its' own make up of the 9800Pro using the refernce design from ATI, the only real way to know if it has a 9800XT core is to remove the heatsink and see for yourself.
Some m8's flash the 9800XT bios on 9800Pro that use its' R350 core. Some have no problems, and it really messes up some cards. I would advise "NOT" to flash a 9800XT bios to your card if it has the R350 core.