Socket are always nice to have. Gemming your sockets is based on what you need in your gear. If you have a nice amount of crit, socket for strength. If you're in Kara or pre kara, socketting for +hit isn't totally bad but there is badge gear that can help fill the gaps making the NEED to gem for hit less desirable.
For red sockets put +str, blue sockets put +crit & +stam, for yellow use +str and +crit. Socket those according to color if the socket bonus is worth a damn, (i.e. Socket Bonus: +4 Crit rating). Also, you can socket whatever gems you want in whatever socket color you want to avoid stacking more of one stat than the other. If you have blue & yellow sockets with a crappy socket bonus and you need AP more than your crit, stack them with str gems, and vice versa.
Once you get 9% hit (so you don't miss ur specials) socket for crit & AP over hit. The gear you get after kara will start to have hit in it, and you can always get badge gear to help with hit.