Of course Ricky Gervais is a star now. But he wasn't quite then. He was on his way up and this makes watching these episodes wonderful. They all have his characteristic humor, maybe not as polished as later on, but hilarious nonetheless. The little in-betweens with Stephen Merchant are great. You can see the chemistry between them.
What I found funniest, most of all, is the fact that he has a line of B (and C)celebrities with which he has to make do. He is still unknown and so probably the A category isn't available to him. You can see his guests all wondering who this short fat bloke is who's slagging them of. Thinking: 'should I take this from this nobody?' He doesn't care. he is sharp and usually goes a bit too far (which is his trademark, I think)in his jokes. Wonderful!