Yeah, I don't see much viable use for sets that try to abuse Gravity for their own needs, particularly when it is just for the accuracy boost. IMO, Gravity should be used as something to set up other Pokes like Mamoswine and Dugtrio who have the potential to be truly threatening under it. If you look at the users that now get the move, it seems that a fully offensive Gravity team could now be somewhat viable.
Below is a list of all the OU-viable Pokemon that get access to Gravity + a useful suicide move (bolded are the Pokemon that can also set up at least one entry hazard, italicized are the Pokemon that could already do this prior to HGSS):
Jirachi
Metagross
Forretress
Magnezone
Bronzong
Blissey
Cresselia
And now for the not so OU-viable Pokes:
Exeggutor
Claydol
The Regi Trio
Probopass
Chimecho
Lunatone
Solrock
Clefable
So there are now seven good OU users that can set up Gravity, compared to just two before (Jirachi and Blissey), who were only really useful for lategame anyway. And how could you ever build a decent Gravity team with only two half-decent users? Magnezone is especially notable as it can also trap and kill Scizor, who is a big thorn in the side of the most dangerous Gravity sweepers. Forretress too for being the only one that can set up Spikes.
Of course, the usefulness of Gravity teams may well be heavily dependent on whether Garchomp gets voted in OU or not. But nonetheless, I wouldn't count out Gravity offense as a viable strategy yet, before it has a chance to be tested with the new additions.
EDIT: I haven't considered Memento here to be a useful suicide option, but if any of you disagree then I can add Dusknoir to the list of OU-viable Pokes.
