True, but if you're Apple you can either spend another $10M on some more server space for one day, or just accept that the early adopters (myself included!) are just going to have a little whinge for an hour or so and then start raving about how good iOS5 is, and when the dust settles 24 hours in no-one will have an issue at all. It's sound business sense, and I can totally understand their point of view.
The problems was Apple let far too many people onto the server at once. They dont need the server capacity to handle everyone at once. but they need some kind of quality of service set up on it and limit connections so those that are connected get a good experienece. If it said when you started "We're sorry the servers are busy, try again later", and then when you are on it you can download at a decent rate then thats fine. The problem I found yesterday is I did the iPad at about 6:15pm and it flew through. I tried the iPhone after that, when the servers were then obviously loaded, and it took me a further 2hrs to download. Thats just @*!# server configuration I'm afraid. They should stress test the servers, decide on a cap on the number of connections and when the reach it dont let more people on.
Needless to say both my iPad (1) and iPhone (3GS) both went through without a hitch once it got past the point it required the Apple servers.