The triumph speed 4 is a very good bike, but the thing I would worry about is parts availability. There have been rumors of triumph dropping the sport bike line, and I know for a fact that the parts can be hard to come by right now, I traded in a 2000 speed triple to get a 599. I hope triumph continues with a full lineup, but looking at where their development dollars are going it does not look good for the sporting lineup.
You know a bike that might be worth waiting for is the Kaw z750, I'm sure that it will be offered next year, and in canada it sells for about the same price as the 599& fz6.