I'm afraid I'm going to have to dissent here. R1 had it's strong points, namely its weapon variety, but the early levels didn't play particularly well, and it did not compare positively to other next generation console shooters. I enjoyed it, but it didn't feel right (for instance, there was no animation from transitioning between the crosshairs and the iron sites -- you just were instantly in iron sites). And the jeep levels were lifted straight from Halo: Combat Evolved, and the tank levels were ripped straight from the Medal of Honor PC games. Maybe PS3 early-adpoters just didn't play a lot of shooters on PC or XBOX, but R1 was decent, though not particularly noteworthy.
Resistance 2 offered a vast improvement over the original in almost every respect. The level design was much more inspired, the gunplay was refined and the iron sites issue was fixed, and the online play, particularly the coop, is what made R2 stand out amongst its peers. All in all, it had a much better feel than the original -- I know this is subjective, but the original just didn't feel modern to me. It felt like a last-gen Call of Duty console game (not the IW Call of Duty games) with inventive weapons. But hey, I liked the ending, so I'm definitely in the minority of Resistance fans!