From what I heard, much of the new content consists of "Adventure Packs" which you buy (I'm not sure if paid subscriptions automatically get access to all of them) and much of it content consists of skins, new powers, etc that you also buy. Subscribers get some but not all of the new skins and outfits. Unfortunately the adventure packs only seem to be targeted to high leveled characters. :/
Champions Online is now starting its first comic book series, and anyone can play them, Silver (F2P) and Gold (subscription) members without any cost.
These comic books mimics something Cryptic has introduced in Startrek Online (that is not Free to Play _yet_). The Featured Episodes there have one contained story-line over 5 missions that are released weekly.
We'll see how this works out for them.
I know that it will be very difficult to convince me to try a new game without free to play. I would not be surprised if overall, the pay-as-you-go might be more costly for me than traditional subscriptions, but I don't care - it's convenience, it is easy to get into it and it is easy to get out. That's worth something to me.
I am not going out to say that I like to pay for costumes and ships and what-you-have, but I think it will work fine enough.
The biggest advantage is really - it costs you _nothing_ to try out a F2P game. Even the biggest hater of item shops will have trouble ignoring all the new F2P games, and sooner or later, they will adapt. And if they don't - no harm done. There are enough people that will only start playing any game if the entry fee is zero that would never habe come a customer before. And at some point, they _will_ spend money in the game store.