A WebmasterWorld thread reports that back links are being updates at some of Google's data centers. The data centers documented with the updated back links are at 126.96.36.199 and 188.8.131.52.
What does this mean for SEOs and your rankings? Um, not much, in my opinion.
Just keep watching your traffic and see what resolves.
Also, this may be a sign of a PageRank update happening shortly. But again, that Toolbar PageRank doesn't show much.
Forum discussion at WebmasterWorld.