The PSU should work for a good number of years. It is important to note that the PSU PCIE connectors listed on Newegg are for one 6 +2 pin and one 6 pin...but that should be fine for most future GPUs you may end up with. And even if you did end up with a GPU that had two 8 pin connections, you can get an adapter that will help with that issue for the most part.
Many GPUs are getting less power hungry, even AMD should be improving on that within the next year or two, so you should be good. By the time you end up upgrading the CPU...and probably the entire system, the PSU should still be kicking.