Seriously doubtful, given the disk space differences. However, I think that now that the losses are reported, we're going to start to see even more future projects and franchises moving away from Sony exclusivity, possibly to the point where there aren't any 3rd-party exclusives anymore. It's already started with as huge and pretty big franchises as Grand Theft Auto, Devil May Cry, Assassin's Creed, and Mercenaries (2 was initially to be a PS3 exclusive), so it seems like the loss announcement would be the final nail in the coffin.
But if you look at those four franchises, something important to notice is that three out of the four are Western developers. Are you wondering why Square Enix remains Sony-exclusive despite the PS3's losses? It's because most Eastern developers stand to profit much more from the PS3 than from the 360 due to the 360's minuscule support in Asia. For this reason, I don't think developers will completely jump ship from Sony, but there will be some major Western franchises that branch out.
I think the more likely trend we'll see is increased third-party Asian developer support for the Wii, given the Wii's lucrative sales and the PS3's somewhat dismal ones. Every developer on Earth has been talking about wanting to do it, but now it's actually profitable for them to do it.