It is impossible for MS to get their money back...  They simply paid R* for the content.  R* is charging for it, and outside of console royalties, MS gets nothing.

Actually I think MS just preordered 50 mill of downloaded copies.  So theyre getting all the money for the first $50 million worth sold. I dont think Rockstar gets any of the first $50 million

Once that number is reached, the royalties will be split in the normal way again, with MS getting some, and Rockstar getting the rest.

At least i think thats how its working.

thats good i been thinkin bout picking this one up but i need to buy halo wars first lol and i have so many games to play as it is so this ones gonna have to wait

The "payment" for the DLC could have come in many forms, like M$ taking less % off the sales of the original game, and this amount was for all the DLC exclusives for GTA, not jsut Lost and Damned, so it's not something that needs to be made up in the first DLC...just like Fallout has several DLCs on tap, so does GTA.