Regarding battery life, something to slide into this discussion.. caching on a Kindle. Just came across THIS APP, so it can be used for caching. Without back lights switched on they are supposed to have awesomely long battery life, I have seen weeks mentioned between charges. Anyone tried caching with one of these yet?

If a tablet is running on Android c:geo with offline maps can be used on it, just like I do on my phone now, but much larger and clearer. No need for and net connection.

Any Wherigo games have any full motion video segments to them? I doubt it as they wouldn't be compatible with GPSrs, but good modern looking interactive Wherigos or similar location based caching games could be made for tablets.