I'd say we got trouble, my friend, with a capital T and a capital V and that stands for... you can figure the next part out yourself. For the first time in decades -- actually, the first time ever -- the Nielsen Co. recently announced a decrease in its estimate of the number of U.S. TV Households. This year, Nielsen is estimating that number at 114.7 million households, down from last year's 115.9 million. At the same time, cable companies are seeing a decline in the number of cable subscribe