There aren't many 1B who are really worth gambling on in shallow mixed leagues for 2007, but here's a list and some blurbs on the guys who I think will make the biggest impacts.
http://www.projectprospect.com/top-3-rookie-1b-06/
Honorable mentions: Scott Thorman, Joey Votto, and Daric Barton.
Are you planning on drafting any of the guys on our top 3 or honorable mentions in your redraft league?