I've noticed that too! However, mine only cuts out when im running on battery. When connected to wall it stays connected (and it has nothing to do with distance from the router, I get great signal from my desk which is where i have my laptop connected to the wall or my bed which is when I run on battery). It stays connected when i'm actively using the internet, but if i stop changing web pages for a bit (to read an article or blog post or something) then it cuts out. At first I thought it was a power saving feature which turns off the airport when it's not being used but i posted a post regarding this exact issue today and so far all posts replying to it haven't come up with a solution.