Have you seen the new Airtel ad with Saif Ali Khan & Kareena Kapoor where he's engorssed in a video game and she wants to download a caller tune on her cellphone? It's a disaster! There is zero chemistry between them, besides the fact that the content of the ad itself is pretty silly. And it shows Kareena Kapoor in all her bimbette splendour! If I were her, I'd be kicking myself in the butt for appearing in such an ad.
I didn't like the Airtel ads with Madhavan & Vidya Balan either. Loved Madhavan, didn't like Vidya Balan at all. I generally don't like her. She's got something very prudish about her, and her character in the ad was so bossy! Especially the one where she's calling her husband from the cab and asking him to clean the house, set the table, make salad etc.
On the other hand is the Tata Sky ad with Aamir Khan & Gul Panag. I don't like their chemistry too much. She looks sort of a misfit with him but overall, the ad works.
Four ads have already been aired, I think - one where he's doing the dishes, the second where he's making tea for her, the third where he's speaking to his mother-in-law, and the fourth where he's lecturing his friend on how to keep one's wife happy! The ads are really witty without being over the top.