Shave the head or grow it out?

i recently shaved my head and got a lot of positive (and negative) feedback from my friends. So i come to ask mfa.

Shaved: http://i.imgur.com/vuHKa.jpg

About 4-5 weeks worth of hair growth: http://i.imgur.com/T2RB6.jpg http://i.imgur.com/b2lXB.jpg

As can be seen my hair is thinning out. (this is what prompted the shaving of the head.)

tl;dr: hair is starting to thin, want advice on keeping hair short, or shaved.