One of my favourite colomnists, Bill Simmons over at ESPN.com, picked Sideways for movie of the year. Here's what he said:

it was probably my favorite movie of 2004. Totally original, extremely well-written, laugh-out-funny, quirky casting, inspired performances, rejuvenated the careers of Virginia Madsen and her breasts ... I mean, what more do you want from a movie?
I want to give a f*$& about something in it, Bill, and I just can't.
Thumbs down.