Another vote for the sony. The Panasonic has a nicer case, but after you live with the Sony for a awhile, then take another look at the Panasonic you'll realize the Sony has a nicer picture. It's hard to see at first glance in the store.
go for the sony, i have a 55" grand WEGA and it is unbelievable, the quality and picture is amazing in HD. for LCD technology Sony is above all competition. hence the reason im gussing sony never put out a line of plasma tv's? my set is a little older, if you can spare the cost, id HIGHLY reccomend a sony bravia if you're looking for something under 42".