For a comparison of how much java/Notch's coding sucks: there's even a well-functioning Minecraft-clone for the NDS...
But even while those clones run a whole lot better, I still want the real Minecraft as you can't play on minecraft-servers with anything else...
Minecraft has become a whole lot less memory-consuming during the last few patches. It now rarely goes over 200MB, whereas I've seen it running out of its GB-allocation in earlier versions. So, apart from not having OpenGL, it is at least runnable...
It's still far too slow though: I've got a athlon64 X2 4400+, and it's currently eating 70+ of both cores running at 1.8Ghz.
Furthermore, its renderer is quite taxing. I've got a GF 8600+, currently using nouveau-drivers, and I've got 15-30FPS, no matter what settings I use. The nvidia-driver was a bit better though.
There are, however, several mods around that make Minecraft less heavy, such as Optifine, But I doubt those can make MC playable on the Pandora...
Yeah, guess we'll have no choice but to play clones...