Considering the already-saturated market that is legal music downloads, it seems unlikely LimeWire will be able to get any traction. On top of that, they aren't abandoning their P2P service – they are augmenting it. You can't sell music legally if no media companies will sign on with you, and given that LimeWire has already spent an ample time in court against many of the big names in music today, it seems the odds are stacked against them.
Regardless, they are making the attempt. The article does mention their intentions to offer a subscription-based service, which could be interesting to see in action. Frankly, however, I don't see their chance of success as very high.