Tranny Leak

after sitting overnight, after about 9 hours, this morning there was a small puddle [about 1 inch in diameter] looked like it was coming from underneath where the tranny pan is. is leaking this much fluid bad? or could this just be needing new seals or something. please help!

(97 blazer LT, 4X4, 150k miles)

Only that much fluid is probably not going to lead to anything catastrophic for normal driving as long as you replace what is lost in a timely manner, but it's difficult to be sure without knowing more about the source of the leak. If it were my truck, I'd find out for sure where it's coming from before taking any cross country trips.