Agreed, you could get a Dual Core in a lappy, but I don't think he needs it. I am also looking for a laptop for my next school, so I will keep reading this thread.
There is no such CPU as a Centrino - Centrino JUST means it's an Intel CPU, certain mobo chipsets & an Intel WiFi card.
An older laptop would have a P4 or Core Duo which were shit - a newer laptop may have a Core 2-Based Pentium, Celeron or Core 2 chip which are quite decent.
"Intel uses Centrino Duo branding for laptops with dual-core (Core Duo) and (Core 2 Duo) processors and retains the Centrino name for laptops with single core (Core Solo) processors. Some of the initial Core Duo laptops, are still labeled as Intel Centrino rather than Centrino Duo."
I'm posting on a "Centrino Duo" laptop. But you could have an old P4 Dual-Core laptop witha "Centrino Duo" label.
Why don't you run CPU-Z and find out? BTW a T5500 is a Core 2 Duo. As Jakg said, Centrino is just a combination of technologies and nothing more. It does not describe a single component in the computer, just that the computer as a whole meets a certain standard specified by Intel.
How about basic laptops with the Pentiums in it (i.e. the GF's Dell or about 40% of the PC's at work) or the ones with Turions in them? (about 25% of the PC's at work...)