The 2.5 ghz was a dual core in that machine but the i7 was a 2.3GHz quad core, it seems there is a bit of an identification issue on some machines it shouldn't make any difference unless you bought it as a quad core machine....
This thread is interesting b/c, I used the apple website to get a trade-in value on my Late 2012 13" MBPro with Intel Core i7-3520M CPU @ 2.90GHz. Based on my serial number it says that my MBP is a MacBook Pro "Core i5" 2.5 13" Mid-2012. The apple system overview and MACcpuID confirm that mk map is infact a 7i @ 2.9. Odd that apple would make such a gross error - not that it really matters.