I watch anytime I see it in schedule, it only started about a month ago. I alternately loath my bad taste or minimise it as a minor guilty pleasure. It doesn't even make much sense as I'm not watching it in any sort of order, sometimes the children are young and Melissa and Joey don't get along very well, sometimes the children are a bit older and Melissa and Joey are dating/married and I've even seen one where she was pregnant (although that may have been a dream, my grip on reality is tenuous re M&J).
It's not funny, the jokes are obvious and dated and often reliant on Joey reprising the "Woah" that he used to say in Blossom. The romance is also pretty unbelievable and clunky. And yet, I can't stop watching it. I really need the new series of Big Bang Theory to start, really really need it.
(It would be all sorts of wrong to buy the box set of M&J so I could see all the episodes in order from the start, wouldn't it?)