during katrina and rita the msm was assuring us that increased hurricane frequency and severity was not a product of global warming  or at least they were assuring us that the data was inconclusive  although i am sure many were wondering  -  this summer was the 1st time i heard about any connection and yes my source was msm again
http://www.realclimate.org/index.php/archives/2005/09/hurricanes-and-global-warming/

http://www.realclimate.org/index.php?p=140

(note the pre Katrina date on this latter).

My overall conclusion:

  • frequency - no way of telling.  A more unstable climatic world is likely to have more extreme climatic events

  • intensity - intensity is directly correlated with surface temperature of the ocean, and that seems to be rising, albeit erratically

A third point:

- one of the articles I referenced above points out the biggest danger to NYC is what I think they call 'North Atlantic Storms' rather than hurricanes.  These have lower peak wind speeds, but last longer and dump more water.

i'm not doubting that this was discussed in the scientific community prior to the disasterous 2005 season   it's just that the msm was telling us just the opposite