What exactly influences the kind of RAM a desktop or laptop can support? Apart from the clock speed, the maximum amount of RAM the motherboard can handle, the DDR type (1/2/3) and the shape of the module (DIMM for desktops, SO-DIMM for laptops)?

I see that in certain cases, such as with the Kingston 4GB DDR3 1333MHz CL9, (and on the Kingston KTD-L3B/4G page) the page displays a set of laptop product numbers.

Does the actual model of the laptop also influence the models of RAM it can support? Could, for instance, an Asus K52 work with that particular RAM module, even if it specifies Dell models?