Does my Macbook need "special" RAM? I want to upgrade the RAM on my Macbook Pro 4,1 A1260 (Early 2008).

Can I just use any RAM of the compatible "type", or does it need special magic RAM because it's a Macbook?

Also, is there any reason I simply must use two identical sticks of RAM rather than one from Company A and another from Company B?
No, your MacBook does not need any "special" RAM.
To see which kind of RAM is needed, visit this Apple Knowledge Base Article. It will show you how to replace your RAM and which one do you need.

Although it is not needed to use two identical sticks of RAM, it is recommended, if your sticks are supporting Dual Channel.