Ngmoco will take advantage of Apple's reversal in decision on allowing DLC in free apps, and they will probably be among the first to do so.
First, In conjunction with Apple's announcement, Ngmoco announced that they will be making their upcoming FPS Eliminate free. The main draw of Eliminate is the thorough online component, with 4-player death match over Wifi or 3G. In the game, you have a certain amount of "energy." While you are energized, playing online earns you credits, which improve your online ranking and can be used to buy upgrades and armor. However, your energy runs out after a few online matches, and while you can still play online while de-energized, you won't earn credits. You can simply wait a certain amount of time (this has not been announced yet, but think somewhere from 1-2 hours), after which your energy will be refilled, or if you're really cutthroat, you can purchase more energy using DLC. This is the only as yet confirmed use of DLC in the game; upgrades and armor will still be bought exclusively using game credits, though extra maps may be available for purchase.
Overall, this looks to be a brilliant move on ngmoco:)'s part. I would be shocked if the game does not quickly climb the App Store charts and reach #1 on the top free games list. This popularity will ensure a huge online community, and there will likely rarely be a waiting time for a match. The downside, of course, is the stress on ngmoco:)'s servers, but with their infrastructure, I imagine they'll be able to handle it. Within the online community, there will almost certainly be an ultra-competitive subsection who will frequently purchase more energy, and this is how ngmoco:) plans to make money.
For more information on Eliminate, see our preview. The game was submitted to Apple about a week ago, and this new development will not affect its release.
In addition, ngmoco has just released a free version of the incredible Rolando 2. This free version includes chapter 1 of the saga, and essentially serves as a lite version of the game with the full version built in. After finishing chapter 1, you can purchase additional chapters for $.99, with the exception of the last two chapters, which come bundled together for $1.99. Strangely, the total price of all the DLC is $4.98, making it cheaper than the standalone version of Rolando 2 which retails at $5.99. With Apple's former restrictions lifted, these "hybrid" lite versions could become commonplace.