If your joints and low back can handle it, squatting has got to be the best thing going for strengthening your legs, and developing "core" strength and balance. Of course I guess your specific goals have a lot to do with it. For me, I am a skier, and I train for general strength and conditioning, and if I can put on some quality mass, then I am happy (after all, heavier things go downhill faster). I am not doing the over the top weights some of you here are probably doing. 315 for 6 is a personal best for me, and I have never tried to get beyond that.
A buddy of mine at the gym is an older powerlifter, who turned me on the the benefits of the squat. He is at the point where he does not want to get any bigger, and feels that he really can't at this stage anyway, so he has given up squatting, at least for a while, and does extra sets of leg presses, and hack squats, along with the the rest of his routing to make up for it. From the look of him, and what he is still lifting, I would be willing to say losing the squats has so far not cost him anything.
I've been toying with the idea of getting away from squats for a period, or indefinitely.
My reason would be knee stress, just can't shake the sore knee - Cissus has done a little but it's still there.
The question is what do you guys think of developing leg size without squats?
Personally I find the leg press to be a superior exercise for feeling the quad and hammies pump and work.