I suppose this would be for telemetrics only (and maybe a video feed) ? It's a kinda cool hack idea but the N900 is kinda heavy to be put a flyer (unless it's a rather large one) and it needs to have unobstructed view of the sky for the GPS to work optimally (CF is pretty good conductor AFAIRecall so it will probably block GPS signals).

Bluetooth will likely be a problem, wifi should not be since you have full LOS (Line Of Sight) and of course you could put a better antenna to the laptop end (actually it might be a good idea to use a base-station [with good antennas] that both the n900 and the laptop connect to rather than ad-hoc).

However the modern radios that operate on 2.4Ghz might get interference from the WiFi (also 2.4Ghz...) so even if you use old-fashioned radio (like I do) if you're on a field with other people it might not be the best of ideas...

I just put a small camera and video transmitter on my RC heli but as stated I have old 35Mhz radio so the 2.4Ghz video tx does not interfere (and I have plenty of flying space on my own "yard" [2ha] so no need to worry about other people). Unfortunately I was paying too much attention to the wrong things (like how well the video feed worked) and touched ground with the tail rotor, stripping gears from tail servo, and things went downhill from there (actually seems I only stripped gears from a cyclic servo in the resulting crash, need to dismantle the rotor head still to check if the feathering shaft got bent)