That's highly subjective. I'd claim that by being allowed to lower prices, the carriers will probably sell more iPads, putting more people in the hands of an abusive company like Apple.
That's probably the short-term effect, however, a potential longer-term effect is hurting the iPad brand image as an elite product and status symbol, depressing demand for the particular brand.
Another potential effect is less outlets selling the iPad, because if there is the potential for others to undercut the price on the same product, it becomes less valuable item in the lineup.
Another potential effect is less sales through Apple's own retail channels if some other outlets are selling below Apple's price but Apple tries to maintain it, which could mean more sales but still less money going to Apple.
