First off, speedbit doesn't actually accelerate the video playback, it does things with the download. I don't fully understand those things, but suffice to say it has nothing to do with making the video playback itself better; better video playback is a side effect of what it is doing to your internet connection (whatever that happens to be... assuming I'm understanding this thing at all)
At any rate, for real video acceleration, there's nothing to find. The Pandora has a Digital Signal Processor (DSP) which is a special processor designed for decoding video and audio very quickly. Many things have already been written to take advantage of the DSP. The problem is that the kernel doesn't provide access to the DSP yet. Upgrading the kernel in Linux is a lot like upgrading your version of Windows (from Vista to W7 for example): with the upgrade you get a lot of new features, but you risk breaking drivers, libraries, and programs, so it is not a step to be taken lightly. I'm sure it'll happen eventually, just need to get more Pandoras out there, and once it does, all the programs that were already designed to take advantage of the DSP will get an automatic speed boost.