Well, when I consider why I bought an n800 it was:

web browsing
instant messaging
voip

Many of the other things it can do are added value to me (I do like having a mini-computer with me to run my own software on).

However, with the iTouch now having mic and etc. it now can do what I wanted in my n800 and if I were choosing today between the two the new (not previous) iTouch would win out.