Well, it depends. If your ready to upgrade right now, then yes, do it now while the prices are reasonable and there are good processors out.
The thing is, none of us really know what to expect from the new processors coming out as of yet. Me personally, I wouldn't wait because, chances are when they do come out, they will be far more expensive, could have bugs and may not perform that much better than what we have out now. Never know till the time comes.
Even right now if you build a machine, it will still be very competitive for the next two years or so. If you have the cash now and just want to spend it, do so.