I think it would be fair to say that Rafael Soriano hasn't exactly made the best first impression in the Bronx. Although his performance has been sub-par, one early concern about Soriano seems to have been alleviated:
The graph, which starts on March 31, 2011, would imply that for the most part, Soriano's velocity has been on the rise. In yesterday's outing against the White Sox, Soriano was throwing harder than he had all season, hitting 95 on the gun with both his four-seam fastball and his sinker.
Note that the cutters on the graph might just be four-seamers with some extra movement on them; I'll need to look at more data to make a more precise split.