if your riding something now and its half way pleasureable, id stick with what i have for one more season. Then drop the cash on the 2015 as long as its redesigned etc etc.
But thats just me personally. I like having the newest of the new things. I ride a 2012 gsxr 1000 now and its more than fun so i have no problem waiting another season. i want the bmw but will wait for a new redesign so i can be known apart from the 2010's and 2012's etc.
What are you ridding now? The current s1000rr is arguably the best in the superbike class period. I don't know if they would change the s1000rr much. Beside, I would wait until the 2nd year after they identify all the issues with the new model and debug them. The 2014 is debugged and refined.
It will take at least year from now to get the 2015 model in but most likely they will release 2015 info by the end of July or August.
and i dont know what bmw will do for 2015 but thay have to update some stuff.....
I don't think BMW have to make any changes but they might. They already updated the bike in 2012. On the other hand, all other 1000cc sportbike manufactures should. Yamaha and Honda were planning to release new models this year but decided not to. Its known that they are testing against the s1000rr and it seems that they still don't have an answer for the s1000rr. No manufactures would want to release a new sportbike and get slapped with bad reviews or be behind a bike that has been out for couple of years. The bike is great as is!
Wow 2015 right away when the 2014 just came out like 2 months ago? But to answer your question, if you are not happy with the z1000 that you have right now and itching for a sportbike then get the 2014. But if you can hold-off for about a year to get the 2015 that we still don't know what the changes are (it may be the same as the 2012-2014 models or better) then you will have the newest model.
Not being biased here since I have a 2013 but for the bike itself as a stock bike and for street riding, this bike doesn't need much changes anymore. So it really depends on how eager you want a sportbike right now since we cannot give any comments on the 2015 model yet...
Do you want LED's under your bike then? LOL. J/K
But if I may, per what I have read on previous threads within the forums, it'll be hard to add hp4 technology to the regular s1000rr's since hp4 will loose it's uniqueness from the norm. But it is not a bad idea to think that they will do it but I do think it is a long shot...