Well, there aren't many details, so don't get too hasty about this, but I imagine that from the phrasing and the lack of details that this is just DLC, nothing more, nothing less. You buy the game, they put extra things online, then you pay to play those things. An interesting thing is that the wording implies that games currently out already can and may do this, but will not carry the emblem. My thoughts are that this is likely Guitar Hero 3.
I imagine that the largest issues involved in this decision were the lack of console space, though we may be able to utilize this content on our SD cards, and an attempt to make the payment plan for these games simple. My guess is that you'll be able to use Wii Points to buy the DLC if you want, but Nintendo will allow each individual game to connect online and charge your credit card, as well.
Anyways, this is not bad news, but rather, mediocre news. On one hand, we can buy new content for our games. On the other hand, this may encourage more developers to leave out content from the final game to make you pay them for it later.