I use 51cm Pompino as my messenger work bike - my advice is to get the Planet X-cross fork so you can fit in proper Cyclocross tires (I am now running 35c Nokian Hakkapeliitta snow tires).

Note the 135 mm rear spacing, which basically means you have to get Phil Wood fixie hub (EXPENSIVE!), a Kogswell or a Goltec. Paul components also plan to make a 135 rear soon. Check out http://www.hubjub.co.uk for more info

IMHO get Avid shorty 4 cantis, much better than mini-v's, which are fiddly, bastard to center correctly and leave very little space between rim and the pads.

Frame is great, though