The rumor makes it sound like two Metroid games are being developed by Retro.

Yeah but it sounds like it won't be out for a while either way.

Also, why delay Mario Kart until next year? It is the definition of a system seller so releasing it this holiday will really ignite sales. 

"Third parties will not change too much on their terms with Nintendo, although there will be a few important multiplatform games that will be at Nintendo consoles too. One of them will be a really important third party IP that will turn exclusive to Nintendo in a similar way of Bayonetta 2 did. It will also create loads of drama like Sega’s exclusivity deal did."

This I find very intriguing because it basically echoes the Dual Pixels rumor from last year:

"Expect more projects like Bayonetta 2 to be announced next year including a partnership that will cause huge shocks when it’s announced even worse than Bayonetta 2."

If true, I'm very curious as to what this is.

because of the deal Nintendo has with SEGA. It would make no sense for Nintendo to partner with SEGA then have all their own IP's cut into the 3 Sonic games SEGA has planed this holiday. They most likely let SEGA have the big push for Christmas and Nintendo will continue the momentum in spring.

I guess so, but I'd imagine that whatever Nintendo could launch would create the momemtum and SEGA could carry it on in the Spring. That would work much better. 

But, we don't know what this "third game" is yet.

I sure hope not as I liked Sunshine the least of all 3D Marios

Hmm as i thought. My purchase (of Wii U) will only come late next year.

Absolutely. But Nintendo has entered into a partnership for exclusive content and is in sense more obligated to make the deal more favorable to partner. Whats more favorable to SEGA..huge Xmas push or ..Spring after Xmas?

Hmm, I guess these deals need to be favourable for everyone. Getting such a deal in the first place was a great move by Nintendo, and I hope that it extends beyond these three games. 

But I guess SEGA would rather have the Christmas push, and coupled with other Nintendo properties and 3rd party titles it will make for a very solid Christmas period.

I hope this is untrue for many reasons.

-I don't know I can stand a other E3 w/o hearing of Retro's title, if they don't show it, I'll be extremely upset.
-I want (and I think WiiU needs) Mario Kart as soon as possible. idc about a Sonic racing game.
-A Bayonetta teaser?! Really?! How many time are they planning to tease us this game?! After that teaser a few month ago, they HAVE to show us a real trailer at E3. Seriously, is there any better time?

The E3 they are describing seems to be a extremely generic boring E3, with Nintendo playing it safe with showing us only the strict minimum that they already told us they would show us (MK, 3dMario, and a little of Smash). If that is really it, and there is no surprises, I'll be extremely upset.

Also, this is freaking E3 for christ's sake! This is the time to unleash the big guns. Yes Nintendo Direct is doing a good job showing us new games. But don't hold on games that are ready to be shown just to show us at later Nintendo Directs!