[Samba] Is samba right for me?

[Chris]

I am currently a college student looking for ways to prepare myself for any
Server Administration job once I get out of college.
I've been going back and worth between Freenode IRC channels (#linux and
##windows) trying to decide what to learn.
On one hand, we have Windows Server 2008 R2, people in #linux keep on
telling me to just go ahead and use it because "samba can't provide
everything Server 2008 R2 does."
The more and more I read up on Samba (especially Samba4; which I realize
isn't going to be released stable for a while) it feels like it
*can*provide all the features Server 2008 R2 does.
Can you do a bit of myth debunking for me?

Would you suggest samba for managing Windows clients (any other tools you
can recommend in addition?)
I really would like to use Samba + Linux because of the cost of ownership
and the open-source community, I just want to make sure it's up to par with
Server 2008 R2s offerings.

Thank you so much for your time!