First off, why would you buy a game like Oblivion for the PS3? You should have known better. I would never buy that style of RPG for a game console, simply because the modability is one of the best things about the PC version.
Because I wanted a PS3 RPG, and more importantly this laptop I'm on isn't really able to run Oblivion. Might do better now that I got rid of the vista Virus that sucked up 45%+ of my processor and 75% of my ram, but still. The Intel chip for graphics isn't much either.
My PC gaming is limited to those developers and publishers who are intelligent enough to shoot for a more commonly available, lower-end PC and laptops instead of the expensive gaming rigs.
Secondly, I bought Morrowind for PC, and felt I paid too much at $5. I should have pirated it, and then I'd still have paid too much. Oblivion was worse.
Finally, I very rarely buy games for PC due to proliferation of viruses being prepackaged with them from the major publishers. I'll generally buy from competent publishers, which means independents. I'm tired of having to replace hardware and reinstall OS's just because of idiots and crooks in an office.
I had Daggerfall, and liked it save for the general bugginess. If I could get it to install, I might have in on my computer now. Morrowind was only slightly more populated than Oblivion. Slightly. It's like the difference between a ghost town and a town where even the ghosts left for better pastures. I never played Arena, again it didn't seem to want to install. Then again, I downloaded it while I was still suffering Vista, so it may work now I have a decent OS.