I liked Resistance 2 a lot, good improvements over the original overall. It did feel a little unpolished in some ways and areas of the game but also had far more impressive highlights over the original. It felt a little like they set too high goals to be realized within a too short timespan. I preferred the original's story telling, but the difference also suits the game well (as in Resistance 1 told as a prequel to "current" events in Resistance 2).
Looking forward to Resistance 3! 
I think the awesome and well polished Killzone 2 as being shown at the time had an effect on high expectations.







