I work there.
650 MPs, only 440 seats, most will attend Prime Ministers Question time, even though it means some have to sit on the steps, if you saw only "40-60" people in the room, it wasnt PMQ,s, they like to be seen on the telly by the people that voted for them, doing thier job.
One session, the debate was attended by 3 or 4 MPs, and it finished early, hense the next topic for discussion arrived before the interested MPs, so they had to shut up shop for a while, as there was no one there.
Tony Blair only ever arrived for that half hour on Wednesdays for PMQs, at the time he was the least attentive Prime Minister we ever had, I only ever saw him 3 times, on one occassion he passed me in the corridor and gave me what I can only discribe as a sheepish and guilty smile.
As Cedars said, its "theatre", I dont even know why they bother having debates, I wonder if any MP has ever been swayed by hearing the other sides view of a debate, generally MPs will do what the whips tell them voting wise, especially if they want to retain thier party seat at the next election. Dogs could easily be trained to run up the relevant voting lobby, thereby saving the country lots in MPs expenses, but then folk might realise we dont live in a democracy after all.
When Gordon Brown was Prime Minister, he who said nobody could have forseen the current economic collapse after he sold our gold, well his Personal secretary who is an MP herself, was chatting to me as I was taking her into the Prime Ministers suite, she said the internet was the best place to get news from nowadays, I replied, "yes, I read four years ago (a year in advance of the sub-prime mortgages) that the bankers were going to bring about an economic colapse, so I invested all my assets in Gold", you should have seen the look of horror on her face, I allways wonder if she told the PM?