Is it possible to have 2 versions of firmware.

I was talking to a buddy of mine who has slightly been following this homebrew stuff. He mentioned that there might be a way to have the PSP read two versions. Like say if I bought a new game that came out and it would only let me play if I had a certain version and had to upgrade. He said that you would be able to have homebrew plus I would be able to upgrade the normal version and the PSP wouldn't notice. I know this sounds incredibly vague but to sound like a broken record I have no idea what I am talking about Thank you.

Thats what custom firmware does. It combines 1.50 and which ever firmware you update to. So you can use all the features from both firmwares.