The i3 is your new hyperthreaded 4 thread vs the 2 thread on the Pentium.
You didn't reveal what you use this for but the i3 wins except for budget issues.
DELL inspiron 1545 blue laptop intel pentium dual core T4500(2.3ghz)
SONY vaio VPCEB1MOE/WI intel core i3-330m (2.13)ghz
which of the 2 laptops is the best 1 to buy i cant dicide.