I had many problems with my PowerBook not connecting to my Airport - it would simply say "There was an error joining the network 'xxxxxx' " Nothing would sort it. So I moved my Airport to the other side of the room and ran the cables and, sure enough, no more problems.
I think my amp was effecting the wi-fi.
Secondly, to have them near each other means having the TV and hi-fi next to each other (cable gives me internet and TV) - not very attractive in the lounge!!