This has been out for over 2 years but with the release of Apple's Airport Express I thought it was important to point out what Apple missed.
The only thing that makes Apple's airport express interesting at all is that it supports music. You can plug it in somewhere near your stereo, connect it to your stereo and then play music from your PC to your stereo. Without that feature it's just a wireless hub which you can buy from other companies for $70.
So, given that the only truly interesting feature is the music feature, is it really all that? Well, in a word, NO. Think about it. You have your computer in the computer room, study or home office room and you have it playing music in your living room. Want to play another song? You have to go all the way back to your computer room. Hands all sticky? Better wash your hands first.
What was Sony's solution over two years ago? The PCNA-MR1. No, it's not a wireless hub. That's best left to a separate cheap wireless hub. What it is is a music AND VIDEO sharing device with remote control.
Plug it in into your PC network and a TV and it has it's own remote and it's own software so you can browse all the MP3s, Pictures and Videos on your PC's hard drive from your TV. No need to go walk back to your PC room when you want to change a song. In fact, if someone is using the PC they can listen to their own music while you, in the living room listen to or watch whatever you want.
Not only that, it also lets you browse your pictures, watch videos and it will even let you use your PC as a Tivo. You can browse program listings from it, select things to record and it will program your PC to record them, from your living room. If you just want to record something you are currently watching on TV you can do that too.
You can even plug in more than one and turn your PC into the house media server. Each one can stream it's own stuff. Pretty awesome!