I dont know what all the fuss is about as I have had GT5 since release date and I have not had one issue with the game. I have done the updates as per my PS3's request but the game has worked flawlessly from day one!!(I have a 250GB Slim by the way). I also have 2 xbox 360's before any flaming starts
I havnt seen that there has really been any problems with GT5 regarding bugs. The only initial problem i saw was that they had set the servers to handle 500,000 connection at once, but this was too little. This was fixed a few days later on, so online play should work fine now.
You might also notice a few technical problems such as screen tearing and a slight drop in framerate for a short moment depending on how much details and cars there are at the screen at the same time, but this happends rarely after my experience with GT5 and it isnt anything game breaking in my opinion.
But as far as bugs/glitches go, i have played GT5 for about 15 hours and i havnt seen a single bug/glitch in the game so far from what i can remember.