I don't think the disparities will be too great, one way or the other. I could be wrong of course...
Microsoft's focus is going to be finding a way to use XBox to springboard a larger push against Apple across other devices, and Sony to use PS4 as a synergistic device to flesh out its PSN environment as a truly cross-device storefront with market appeal. Living room and all that.
For better or worse, we need to understand that Apple looms like a shadow over this whole thing for both companies in the context of their broader objectives, and resources will be dedicated accordingly.
With regard to traction, I think both console makers are banking at least to some extent on loyal fanbases to ensure things get going - and I'd say that's probably a safe enough bet to make, assuming reasonable launch prices and decent titles.