I think it has to be Pujols. The only knock against him is lack of steals, so some could make an argument that Soriano is the more valuable fantasy player, but I think Soriano is too streaky and you can cheaply get a Crawford or Sanchez for the steals. Next year, Pujols will only be 1B/OF eligible, but I'd still take him first overall, as his overall production is better than ARod's, especially with his sky high average.
My top 10 fantasy players:
Pedro is the only pitcher I put there, because pitchers are just too injury prone and inconsistent to risk a first round pick on in most cases. Just look at the injuries to RJ, Schilling, Pedro, Morris and Oswalt and the big time drop offs of Lowe, Zito, Colon, and Miller this year. Pitching is so much more unpredictable than hitting that you're better off getting top notch hitters the first 2-3 rounds.