Generally speaking a 2nd gen Core i3 CPU is on average 10% - 12% more powerful than a 1st gen Core i3 CPU based on various benchmarks; that's assuming both CPUs have the same clockspeed. Therefore, the 10% higher price is justified by the benchmarks.
Additionally, the 2nd gen Core i3 has better integrated graphics (Intel HD 3000) which is actually decently capable of playing games which are that very demanding like Mass Effect 3. That is if you plan on playing games...