I have a 15in macbook pro bought in Oct 2008. Originally I intended for it to be my "extra mobile" computer, but within a month, I had converted to using it exclusively while my custom built PC desktop collected dust.
Once you realize how a mac works, you start to "get it" and then it's easy from there.
As for documents, I suggest open office from openoffice.org it is free, it opens word docs just fine and saves them the same way and can then be opened on a pc with no problems. Unless you are doing super complex stuff, it works great, it is less bloated, and free!
I think it's worth it to get the pro because you might not think you need more memory now, but eventually :might: have to upgrade. In general, the more the better when it comes to that. I run so much stuff on a daily basis, it would boggle your mind. I need a pc for work so I run Windows XP in vmware fusion within the mac os, plus all my personal programs plus a remote desktop connection to another computer for forex trading PLUS if I really want to, I can play world of warcarft..all at the same time. 1.5 years with this computer and no noticeable slowdown to speak of, and that's coming from a techie. I don't anticipate needing a new computer for quite some time, although the imacs do tend to draw me in /drool