Would a game made with SDL in C++ be able to be "pitched" to Microsoft as a candidate for an Xbox Live Arcade game? It seems to me that nearly anything can be ported to XBLA.
I know that this would be a very ambitious goal, however I am entirely confident that my game would be "good enough," I'm just a bit unfamiliar with certain technical aspects when it comes to video game consoles.

Yes.

However, you don't pitch XBLA games to Microsoft - XBLA only cuts deals with recognised publishers, so you have to pitch your game to a publisher first, who can then pitch it to Microsoft.

You can pitch it the the publisher "Microsoft Game Studios", but they're a different company to the XBLA people, so it's the same as pitching to THQ, EA, etc... i.e. After pitching to "Microsoft Game Studios", they'll have to negotiate a deal with XBLA just like any other publisher would (and can be rejected, like any other publisher).

Also, for a publisher to accept a pitch, they'll want your team to have to know-how required to deliver the product, which means someone with the ability to do the conversion from PC to Xbox - you'll have to hire someone with this experience.

I had the same problem with Wii...
You need to find a company which must be registered by Microsoft (Nintendo in my case) and cooperate with them.
They will be your partner and MS must approve "their" game - it is simplier if they created some games and have some negotiation experiences.

Does SDL run succesfully on XBOX?
I tested this personally on my home Wii to be sure there are no problems with it and then I started to looking for partner...

SDL does not run on XBLA and likely never will, unless someone crafts a C interpreter for C#

But there's no reason why an SDL-based game couldn't be used for a pitch. But why use C(++) and SDL when you can save yourself loads of time by starting with C# and XNA?

SDL does not run on XBLA and likely never will, unless someone crafts a C interpreter for C#

But there's no reason why an SDL-based game couldn't be used for a pitch. But why use C(++) and SDL when you can save yourself loads of time by starting with C# and XNA?

XBLA does not require use of C#/XNA. Most XBLA games are developed against the native XDK using C/C++. XBLI is the channel that restricts you to C#/XNA; for XBLA it is only an option. 'Schizoid' was the first XBLA game to be released that used C#/XNA as it's primary development platform; how many XBLA games were released before 'Schizoid'?

This seems to be a very common misconception about how games are developed for different segments of the service. XBLI == C#/XNA. XBLA == (C#/XNA OR Native XDK)

That said, I don't know enough about SDL to comment on how readily it would run on an Xbox 360 via the native XDK.

I'm guessing that nfries88 just mixed up XBLA and XBLIG/XBLCG

SDL is a very portable API, I would expect that if someone had the time, inclination and the relevant access they could create an XBox backend. Depending on how similar the provided APIs are to existing Windows APIs, this could be quite manageable.

SDL is a very portable API, I would expect that if someone had the time, inclination and the relevant access they could create an XBox backend. Depending on how similar the provided APIs are to existing Windows APIs, this could be quite manageable.

Pretty sure that even if they did, they couldn't release it because of NDAs and stuff.

@XBLI vs XBLA: I guess I was a bit misinformed. Still, I'm assuming that this is an indie development team here, so wouldn't they be working on XBLI anyway?