Rock Band & Guitar Hero compability

Is it possible to make an app that let's you play Rock Band with Guitar Hero guitars (and in the future microphone and drums)?

Prolly not

not a homebrew program at least, it would take either hacking the guitar, or hacking the disc in to thinking each other is the corect rremote/game, but then you run into the problem that guitar hero guitars arent the same as rockband's

No. That would require getting all of the source code for rock band (which would be illegal) and rewriting the input segments. Then releasing a download so large you would need at least a 5gb SanDisk to even use it.

I just thought the possibility of using cheats somehow would make it possible.

It'd be one huge cheat, and even then it would require someone taking a many sleepless nights pouring over a hot hex editor and a few gigs of bytes. All so that a few people didn't have to go out and spend $40 on a new guitar controller.

Wait for Guitar Hero 4.