The game is still in Beta, I am sure they will come out with come optimization for lower end computers, after all it is just a bunch of 16x16 block were talking about, nothing like some of the flight sims I run on my laptop.
Same here i have 3 computers, all lagging.
Wish notch would have told us we needed super computers for the update, i would stayed at 1.7
Great job on 1.8 but it just irritates me to no end that i cant play it on any of the 3 systems.
I've actually noticed a solid increase in performance.
I went from 75-90 in 1.7.x to 95-140 with 1.8.x
All settings max, also running the server we play on.