While I have not looked at the ubuntu software center sense 10.04-testing I am not sure but I think you can update from there.
If not and you have Update Mangler enabled it will update the list itself on the schedule you choose in Software Sources. It will also upgrade your system by it self which can be very interesting at times.
There are many of us that used to use Ubuntu here and no longer care if they improve it or not. The reason that they want all the automatic things like UM enabled fully is the very idiot noob to whom you refer.
I have some trouble with this because I came to Ubuntu straight from MS and had no trouble at all learning how to run and update/upgrade cycle, using synaptic first and then learning the joys and advantages of the terminal.
Admittedly the terminal did not intimidate me as I started my computer use with MSDos and thought they did nothing but go down hill from there on.
Linux gives you a nice gui environment and a great terminal. All you need do is read the manual. I really don't think that folks leaving MS, or Mac for that matter, are afraid to try something new and learn something new. If so, why would they change what they are using now?
The problem Ubuntu has is that they are bound and determined to assume the mythical average user is as stupid as MS believes them to be.
I was lucky to start with 8.04 (horny horse), 8.10 never blew my skirt up, 9.049jumpin jackass) was great, 9.10 (kinky kitty) was all right, 10.04 (lounge lizard) was plain evidence that the rot had set in.
Your idea of switching to a different distro is a very good one. I suggest one that actually wants to be Linux. That would be about anything but Ubuntu and its offspring.
If you want something that has been user friendly for a long time I would suggest PCLOS which is a RH branch OS using their own script to use apt for packagemanagement including synaptic.
I have also just discovered Saline OS which is based on Debian testing using Xfce. It is pretty nicely set up although I did have a problem with Software Sources being a little funny. Turned out to be that /root/.synaptic/synaptic.conf was calling for squeeze instead of wheezy/sid. Do not know if that is common or just a glitch in my install.
Mandriva has also been pretty good to work with.
Mageia which is a fork of Mandriva looks even more promising.
Debian itself is, to me, the best of the bunch. Yours is, however, the choice. This is Linux after all.
A good place to start;
http://distrowatch.com/dwres.php?resource=popularity
Their homepage is a good place to find out about new distros.