As long as they can be disabled to not ruin my jailbreak I see nothing wrong with them. Considering how large the update files are though I can't imagine happening too soon. If carriers have a problem with streaming movies over 3G imagine a 600MB update.
how does Android do it?
Android updates are significantly smaller. They also occur far less often. iOS updates are released fairly often with one or so a month. An Android phone might have one or two large updates throughout its entire life. The entire Android OS is relatively small though, the Gingerbread ROM I have is only 95MB's.
Just because IOS updates HAVE been large does not mean that they will ALWAYS be large.
I suspect IOS 5 has some fixes in this area. The downside will be that you'll have to be on IOS 5 to get the benefit.
Also guessing it may not be OTA updates but rather served over Wifi only to keep impact the the 3G operator's networks down - and also to avoid people smashing into their download caps.
It looks like we will be waiting until the iPhone 5 with iOS 5 is released sometime in 2012.
I'm not kidding (I wish I was). The reports around the web today are emphatic that the new phone will be called iPhone 4s and only have very minor improvements.
So it's another year of glass, a flat featureless style and a tiny 3.5" screen. Oh well, for those who like to think small they will be quite happy. They are getting their wish, that a larger more usable display is not going to be appearing until 2012.
Actually now that I think about it, the majority of iPhone users wouldn't be able to do this... iOS updates are pretty big and for all those with a limited data plan, this would not be a realistic thing.
Damn people with unlimited data! I'm jealous.
Does Android patch their OS as opposed to having a new OS downloaded? (i.e. they just put a patch over the user's current OS, whereas iOS is downloaded completely and then installed on the device) I have always been curious about that...