Yes you can cash them out - as said previously - go to your account page on the site and open up the points tab.
From memory you need 10,000 points and (dont quote me here

) but i think it is $10 for every 10,000 points.
Sounds a lot but once you are in that area of points you should be picking them up quicker due to your higher ranking on the site (length of time played etc)