i'm not familiar with very many indie games that even have DLC. the only one i can think of is cliffski's gratuitious space battles. are there even any others besides that one? EDIT: spacechem also had one. so that's two. and the binding of isaac had one, so that's three.
because it's so uncommon to have DLC for indie games, the chance of getting sales stats for DLC for indie games is pretty low. you're better off relying on stats for DLC's for AAA games really
and from what i know about those AAA game stats, typically 25% of people who buy a game also buy the game's DLC's, although this can vary quite a bit, especially if they're offered in a bundle / game of the year edition, which many are
personally i wouldn't really consider making a DLC for my games unless the original game sells hundreds of thousands of copies and there's a large demand for it; it really wouldn't be worth the time otherwise, i'd rather be working on a new game instead
In addition to those you mentioned there's AI War, though I'm not sure if its DLCs should rather be called expansions. I have also been looking for data on AAA DLC as you suggested, but most publishers like to be secretive about it. There are some statistics available for consoles, but PC stats are much harder to come by.
I know there will (sadly) be good ideas for features that we need to leave out of the initial release because of a tight development schedule. As long as there's food on the table we would be happy to make some of those features available as updates and DLC.
If you want to include dlc in your games big, bulky, hairy men will wait you in your bedroom at night to make sweet love to you relentlessly poking around until they enter your secret place.
Yes, you are mean.
But, if your dlc is an expansion with decent content in it, by all means. If you plan on charging friggin' colorful hats and suits, I'll call eva to talk to you with severe grammatical errors and all.
Let's hope that's not gonna happen.

We are planning on additional game modes, new units (or in this case buildings) and tech tree expansions, all of which should allow for even more variation in strategies and tactics. Price point will probably be 3-5$/DLC.
Also thanks to both of you who mentioned Cliffski's, I came across this
interesting post about DLC pricing while checking the blog.
