I would say it's foundations are getting its first significant significant antisense drug approved. The proof that you can get antisense to work well enough to get FDA approval suggests that it can be used for other targets as well. I expect this to be just the beginning of a number of approvals for Isis over the next few years. I know that there has been this promise before with Isis, but they finally appear to have gotten the efficacy high enough and the toxicities low enough that there are diseases that could benefit from targeting specific drivers of the disease.
Additionally, based on their recent Cell paper (2012) they might have made a breakthrough in bringing siRNA therapies closer to reality, which could be even more effective than their antisense. However, those potential therapies would probably be a number of years away from trials, but exciting nonetheless.