Look in the mirror.
Valid question. One that frankly I could debate for hours. Here's a brief summary.
I truly need (due to my work) the most resource laden laptop available, therefore I have always upgraded at each new release, over the last decade. If experience has taught me anything it's that speed, or any other "advantage" of upcoming new chips always looks better on paper than once you have the machine in front of you, in use.
I'm not saying there is no value to waiting, if you truly do not _need_ a computer in the relatively near future. But you will always pay in a variety of ways for "the latest". Sometimes in the amount of bugs present in a new model.
So, setting aside the lure of the lastest, and greatest. Ask yourself if you've not better off buying the current machine.
Cheers...