I read that shortly after I posted the previous post and I would presume it's the same with any kind of paste, as even though I do have Arctic Cooling paste around instead of Arctic Silver based on googling I haven't found any difference between how to apply the two pastes, only difference is pretty much their respective performance, burn-in periods and so on.
On the other hand it seems like vertical method is recommended for i7 CPUs.
Edit: On the other hand this seems to disagree in general:
http://www.hardwaresecrets.com/article/What-is-the-Best-Way-to-Apply-Thermal-Grease-Part-1/1303/1
Sounds like a better option to put a small blob in the middle instead.