Re the post from Sallyc. I have been going to Cuba on and off since 1997 and was last there in March 2014 with Travelsphere. The tour is exactly the same as Just You save that we did not get to Hemingway's house as it was closed for filming. I had been there before so was not too worried about that. It turned out that I had in fact been going to Cuba for longer than our TM!!
There have been immense changes since 1997 and since the country was opened up for tourism - hard currency. I did my first full tour in 1998 when there were a dozen or so of us in a mini bus. When we needed a comfort stop or a coffee etc we just rolled up at the first likely place that looked as though they could serve us. This last trip there were purpose built tourist way stops for the multitude of tour buses criss crossing the island. Also the open top bus tour in Havana was a new one on me. But don't let that put you off. Away from Havana (and the beach resorts) the country is largely unspoilt and Trinidad is an absolute must.
As for an American influx - they are already there in small numbers on cultural tours but these were the ones who had a real interest in the country & the people. Companies like Just You work well ahead on bookings for hotels etc and it will take a while for the American trade to build up but I am guessing the first pressures will be on the beach resorts of Varadero although what knock on effect this will have remains to be seen. I would expect 2015 bookings by UK companies to be safe and the first impact may be for 2016 tours when American tour companies may be looking at setting up their own trips.
October is the end of the hurricane season but I have been there several times in October & only had one hurricane incident. I got a nice certificate from the tourist board which says I survived Hurricane Irene - which by the way, and in a very Cuban fashion, arrived before the electricity had been restored.
Go whilst you can and, as go with the flow.