See, now THIS one I am less wary over. Newsarama has a good interview with J. Michael Straczynski where he discusses the move (that's where this neat promo image came from, as well!).
The Archie heroes are fine heroes, in and of themselves, but unlike the Milestone heroes, they're not tied to one specific universe, as already noted by the !mpact experiment of the early 90s (which had some really good comics, notably the Black Hood and Waid's The Comet), so they're basically blank slates for Straczynski to attempt to work some magic on.
I'm looking forward to their usage in The Brave and the Bold. It sucks that he's able to get the usage of characters from a whole other comic book company, but can't use Vertigo character. Feh, I say! FEH!
By the by, who drew the promo piece? Is that Joe Bennett?