Next year meaning fall 2013 or fall 2014?
If you are talking about fall 2013, then I would wait for Haswell. The is supposed to consume a little less power than current Ivy Bridge mobile CPUs. But it wont be like day and night difference. I believe the most energy efficient Haswell CPU ("Y" models) is suppose to be 7.5w but it will be giving up a lot of performance to reach that low power consumption. The "U" model Haswell CPUs used in most typical ultrabooks are expected to consume about 15w of power compared to 17w for current Ivy Bridge CPUs. Battery life also depends on the capacity (size of the batter). If you stick a smaller capacity battery with a Haswell CPU, it might have shorter battery life than a slightly larger battery with an Ivy Bridge CPU.
If you are talking about fall 2014, then I recommend you wait for the Broadwell mobile CPUs. That's assuming you don't need a laptop this year.