It seems that way. I'm sure Bethesda will offer an "old-school" camera in Fallout 3, similarly to how Rockstar put a GTA 1 & 2-esque camera mode in GTA 3 in order to keep all of their fans happy.

As for getting a new computer, Fallout 3 uses the Gamebryo engine (which they also used for Oblivion). If your computer runs Oblivion well, it will most likely run Fallout 3 just as fine.

"Stephen Wolfram is the creator of Mathematica and is widely regarded as the most important innovator in scientific and technical computing today." - Stephen Wolfram