Well yeah, except no one could really forsee Microsoft and how they do on the marketplace.
If Nintendo can pull off some kind of crazy new blockbuster franchise/craze (we're talking Pokemon-sized here), they may have a shot at the PS3/Xenon ... I'll give them that much, otherwise I'd say no way.
Mario/Zelda/etc. as is isn't nearly enough, and really you can't expect third parties to build audience for Nintendo -- Capcom is jumping off that ship as fast as they can, and I think other third parties will take a good look at that before commiting a big exclusive in the future. I mean sure there will probably be collaborations with Namco and Square-Enix in the future, but not the kind of situation where Nintendo gets an exclusive like Final Fantasy XIII without first showing they've built an actual userbase.
I don't believe for a second that Microsoft will not take heavy losses on the Xenon initially either. They have to do it, otherwise the PS3 will badly outperform them. The difference is by virtue of their deal with ATi and dumping components like the HDD, they're not trapped into a hardware (like XBox 1) where certain components like the HDD or GPU never go down in price.