I found the irregular facing rules to be a pain in the butt and really dumb in 3.0.
I had a Giant Centipede face my party... he's 15' x 60'. I had to figure out HOW he would actually take up that space... how he MOVES is complicated enough. How do I move a space like that around the board... and keep track of what squares he actually MOVES through, who he provokes AoO from and so on.
Plus you have the stupidity that his sides and rear are defined... unlike everyone else. So I ruled that this centipede only actually THREATENED the squares around the front 3x2 section of him... the rest was just legs. Now, if I just went by the rules, he threatens everything around him, so he can make bite attacks against creatures by his rear. Huh?
Removing facing from irregularly shaped creatures is good. It was either THAT, or add facing rules for everything, which makes the whole game more of a pain to keep track of. How they DID it, I'm not sure about, and I think I'll have to get used to it.
Like Dimwhit said... suddenly my Centipede would take up most, if not ALL of the room he's in. The penalties to attacking while "squeezed"... seem odd. They work for an Ogre, which is just large. But what about a giant centipede fighting in a tunnel? Certainly he should have some kind of advantage, and not have to "squeeze", because he's not wide at all, he's long! However, from what I've seen of the 3.5 rules, both the Ogre and the Centipede will suck a big penalty from being in a tunnel.
It seems really odd now. In all honesty, I'm going to have to play with it, and perhaps I'll learn to live with it.