I have Nokia 770 tablet at home. It is mainly used to play Maemo Blocks, Mahjongg or other game. From time to time I use it to browse web or read RSS feeds so it is non-stop connected to my home WiFi.
But today I had to charge it in the morning and after that it died after 2-3h of playing. I do not know how good is N800 in this subject but hope that next tablets will have better battery life as this one has it too small.