zhemis said:
From http://left4dead.wikia.com/wiki/Campaigns
Cold Stream ― an upcoming DLC Pack which includes a non-canon campaign with ported versions of Death Toll, Dead Air, Blood Harvest and Crash Course.
And the announcement from the l4d2 blog:
http://www.l4d.com/blog/post.php?id=5019
If that's also going to be on 360, fantastic. I love having the option to play l4d1 games on l4d2, but still, I do occasionally come back on l4d1, because the amount of extras added to l4d2 make it feel quite different, and sometimes I like to go back to basics. On 360 there still always seems to be a significant amount that play l4d1, strangely. I assume yours is the steam version?
I suppose my point is, I think there'll always be people who prefer l4d1, no matter what. How many remains to be seen.
As for getting l4d2, I think it's worth it. Just. My version wasn't censored, mind you (I'm in the uk). L4d3, however, would probably be pushing it.