As far as I'm concerned, the changes that Valve implemented are positive for balance. I know I'm in a serious minority position here, but in considering the intended use of the various classes, it makes perfect sense.
The Soldier is an offensive class, meaning that they should rush in and cause as much damage as possible. That doesn't mean that they need to rush in foolishly, and it takes so dang long to reload the rocket launcher anyways that a skilled player can use that time running to the next ammo box or picking up the weapon of a dead foe. Carefully managed, I don't see that the soldier need ever run out of ammo, but lowering that threshold encourages more efficient play.
As for the demoman, I am the first to say that I loved having more bombs and stickies than I knew what to do with. I could cover a wall with stickies, decide that I didn't like the pattern, blow them up, and start again. It was also a habit of mine to keep firing stickies until I had two or three crits up there. With lowered ammo, I can't do that. Also, consider that the demoman is a defensive class, and should (ideally) be hanging back and providing coverage to the offensive and support classes.
My gripe is with the implementation of the Custom/Internet tab and poor server filtering, but that's a topic outside the scope of this particular thread.
