Hey let me give you guys a little heads up on some of these sites:
Yahoo is probably still the best in terms of offering updates and such, and I like the new drag-and-drop layout, since the classic can be very tedious for head-to-head.
I do auto-drafts, and the Yahoo system works well. ESPN, on the other hand, will draft you like 6 outfielders in a row, and will only fill empty roster spots with the last pick - which is totally useless for roto, for example, and means you have to constantly trade down. Yahoo is much better at giving you a balanced roster. So no auto-drafts on ESPN.
ESPN - last night I noticed that they give you, in brackets, the opposing starting pitcher (probable), which Yahoo does not. That's really valuable for H2H because you can really choose your matchups if you have two guys with near-equal value and much different pitchers faced.