If they bring in a better notification system and lock screen, that itself would be a good enough reason for me to upgrade to iOS5/iPhone5.
The writer's on crack though, if he thinks Apple is going to reverse their decision about sideloading 3rd party apps or integrating Gmail features into the mail client.
I don't think it's a definite that there will never be sideloading of apps from 3rd party sources. At a certain point — perhaps when every carrier, every country carries the iPhone, or perhaps when there are a full range of iPhones (similar to the current iPods), or when the hardware innovation stagnates to the point of ongoing incremental improvements with occasional substantial improvements (like the the MacBooks) — being able to offer sideloading from the non-Apple app store may bring in a whole bunch of "advanced" users who wants to achieve what isn't possible at the moment.
At that point, the Apple app store will be so established and prevalent and known to the masses that unless you really needed to, you wouldn't use sideloading: not unlike how Apple app store and the JB app stores exist now, but officially.
Who cares about 'advanced' users? There's so many less of them than normal users.
Do normal users actually pick devices based on being able to side-load apps? If yes, then I'd eventually expect to see it in iOS. If no, then I'd not expect to see it.
For what little it's worth, I think the answer is 'no', but that's based purely on my personal experience and could well be wrong.
The writer's on crack though, if he thinks Apple is going to reverse their decision about sideloading 3rd party apps or integrating Gmail features into the mail client.