I have a netbook with a single core Atom chip (N470). I wonder if I can change the CPU to the newer, Dual Core version of the Atom chip. Would they both have similar number of pins? If so, would the latter easily replace the former?
More often than not, especially with the Atom processors, the processor is soldered to the mainboard, so the chance of doing a drop-in CPU upgrade is not very good unless you are a genius with a soldering iron. With some of the i5 and i7 series processors, though, you might luck out and get a socketed processor, bu the chances of this with a low cost laptop are next to nill. You have to go a bit further up the food chain to get that kind of build.
Atoms use a package called BGA559 and is soldered onto the Mobo, unless your skills with a soldering gun is so good you can precisely connect 559 dots that's no bigger than 1mm each to the respective places on the Mobo, Imafraid you cant.
For upgrading possibilities however, almost all non-ULV processors uses a desktop0like socket called Socket S1, but even if you manage to get the CPU in, the BIOS is another problem.