I think if you've invested in a fancy 'smartphone' like the Centro, you're probably not going to see as much use for an NIT. Sure, the Centro isn't as capable as the tablet, but it's capable enough, and there's a lot of overlap in functionality.

Disclaimer: I do not own a mobile phone of any type. Unless you consider VoIP-from-tablet or IM-on-tablet "having a phone".

EDIT: I use my tablet for tablet-things most of the time (music, video, games, sketching, internet browsing); BUT it is really nice to be able to do laptop things for the times when I need it to. Yes, OpenOffice is ugly on the tablet's screen, but it is nice to have all of that functionality for the times when I really need it.