Visto has their own patents. They licensed NTP's patents for their own product so that their product would be compliant with those patents. This is a big concern right now and RIM will likely license the patents from Visto. However, working on RIM's side is the fact that Microsoft was the first company to be sued by Visto and there's a lot of money backing Microsoft on the issue.
With that said, Visto already successfully filed suit and won against Seven Networks for their product. The significance of that lawsuit was the fact that Seven Networks was formerly a firm in Europe who's development team went to Microsoft to build Magneto/DirectPush - see any issue there? During that case, Visto's patents were put through the USPTO process and many of the arguments and points were upheld.
RIM has likely been ready for this lawsuit for quite a bit, to be perfectly honest.
Read this article - might help RIM and other companies with prior art arguments against Visto's patents, which were awarded in 1989, if I'm not mistaken (maybe the early 90's though). [2006-04-16] In Silicon Valley, a Man Without a Patent