A few weeks ago I did my 25,000 mile oil change and, on a whim, I picked up the Mobil 1 oil filter with my Mobil 1 oil. I'd used a Fram filter the previous couple of times.
Last night I saw a link to this Engine Oil Filter Study. Having read it, I'm never touching a Fram filter again...ESPECIALLY since some of them actually have Teflon powder in them! I'm sticking with the Mobil 1 filter, synthetic filtration for synthetic oil