If you remember back when iPhone firmware 2.0.2 came out an option was removed from the App Store, you could no longer “Update All” from the iPhone. This feature seemed to be disabled because it was causing some of the problems with buggy apps and nearly constant crashing (I didn’t have those problems of course).
But, with iPhone firmware 2.2 the option has returned (unless I missed its return in another firmware version). This doesn’t tell me a whole lot but Apple seems to be quite a bit more confident in the iPhones ability to install software cleanly.
Back when it was first removed I was certain that this was one of the major troublemakers for all of those crashes but I haven’t heard nearly the complaints that I used to about crashing apps and I think Apple is maturing the platform very nicely.