What's annoying about it? It only takes two/three taps:
1. App Store
2. Updates tab
3. 'Update all'
A password isn't even required anymore. Personally I don't see how anyone could find that annoying but even if they did most app updates come with new features and the benefits of those far outweigh the 10 seconds of time it took to update.
1.) Installing applications of size X generally requires 2X amount of space. I'm not a dev so I don't know what happens under the covers, but I can understand why (copy compress package, unpack/uncompress and deploy to filesystem)
2.) When you update, it's an all-or-none proposition with the "Update All" button
3.) Because of 1 & 2, if you're low on space and one application is too big to update, when you press the "Update All" button you get an error message and nothing gets updated
So, I now have a red "93" on my App Store icon, and unless I want to manually go and update each non-big app individually, that's how it's going to stay.
Bonus: Loading the icons in the "Update" screen impacts the UI something fierce (as does updating, I guess), so Updating individual apps is an exercise in frustration. This scales linearly with the number of apps you need to update, so at this point I'm past the point of no return and will likely not update an app unless it complains directly to me. Even better, finding the app in the update screen is painful since they're sorted by time and not name, so it's nearing the point where if I can't use your app because you complain to me, and you're not an absolutely essential application, I'll probably just delete you.
Think about needing to use an app when you have 10 updating and it is the last in the queue. Remember what computers are for, for getting to information you need.
If you tap an app icon while they are updating it will be given priority and moved in front of the queue.