This has been covered by several other bloggers - Chris of Stale Gum has his comments here - he once again campaigns against gimmicks and brings up some other interesting points regarding insert flooding and other issues.
The 9 page Topps Sell Sheet can be found here.
My first impression is that the base cards are too bland too white. They aren't as boring as 2012 Topps but there is not much interesting in the design. It is a design w/ potential. The Parallels on the sell sheet do pop a bit. They stand out after seeing the minimalism of the base cards. The blank borders on 2013 Topps seem even larger then previously releases.
Recently the teasers have featured a lot of Phillies including Ryan Howard and Roy Halladay. For 2013 quite appropriately after their tough 2012 season, the current Phils have been banished. Topps did reach back to Mike Schmidt to show us what one of the relic inserts will look like.
Are there any Relic Collectors out there?
The first relic I pulled when I retunred to collecting was exciting. That was the last time I was excited about relics. The Schmidt card above is fine enough looking but other than noting he is a Phillies player nothing about seeing it on the sell sheet makes me look forwrd to 2013 Topps.