Both a NIT and a laptop have their pros and cons, personal, depending on situations. They both have their niche, and the hardware in both devices is also important in order to do a compare.

I'm not sure if this is an option for you, but my project is to have a 24/7 desktop running on a server and using SSH and remote desktop (NX) to connect to it using the mobile device (NIT or laptop) rendering the mobile device into a thin client. Besides that, I will route the traffic over VPN to this server. Initially the server is behind a Soekris with running BSD & PF + AltQ. Later, the server runs on 100 mbit. Therefore, instead of running MicroB on the NIT, I'd run Opera on the server containing all my bookmarks, settings, and so on. Issue is, not 24/7 connectivity with WiFi. Could be solved with tethering + 3G.