Advice on World of Warcraft (might get flammed)

im thinking of getting it but the only version apparently available is this: http://www.amazon.co.uk/exec/obidos/ASIN/B000197Z30/qid=1130793870/sr=1-1/ref=sr_1_10_1/026-7513293-5972400

now is that 1 version compatible with both Windows XP and Mac. cause if not i dont have a mac?

also how much does it cost to play online?

http://www.amazon.com/exec/obidos/tg/detail/-/B000067FDW/qid=1130798722/sr=8-1/ref=pd_bbs_1/102-8365610-2383317?v=glance&s=videogames&n=507846

Looks to me that they made one combined version. As it says both platforms, it works on both.

its about $15 per month.. but there are multiple payment methods available