Word of mouth is the key thing in generating want-to-see and future revenues for your film. You want to shape that conversation as much as you can.
It once was that film critics truly helped shape these discussions, but most have them now have been fired and lost their platforms. Even before that, many had shifted to a simplistic way of reviewing, reducing things to a yay or nay and a synopsis. But whom is doing this now? There certainly is a galaxy of film bloggers out there. And they are a lot easier to reach than their prior generation of film critics.
If you got your film into a major film festival, I am sure the blogosphere will want to hear from you. But why not go that extra step and get them a DVD in advance. It's hard to see more than 25 films at Sundance and since there is five times that amount there, why not make sure that they see yours in advance?