Why is everyone up in arms about Redfin?

OK, so I don't have all the info about Redfin, but man are they causing a stir. Every Seattle Real Estate Blog seems to have something to say about it - including Redfin, which has their own blog. Here's what I know:

• They've pissed off the traditional real estate agents (I think I like them already)
• They place a lot of their marketing eggs in the internet basket (i.e. they are an online business)
• Their President & CEO, Glenn Kelman, has testified in front of the Congressional subcommittee on Housing and Community Opportunity
• They currently only do business in Seattle and San Francisco

Since my knowledge is minimal, I thought I would post the various blog posts and articles that comment on Redfin:

360 Digest - Marlow Harris

Redfin's Response to Marlow Harris

TechCrunch on Redfin

Seattle Times Article on Redfin

Real Estate 2.x "Redfin will flop like a fish out of water"

Rain City Guide

New York Times: The Last Stand of the 6 Percenters

I've Joined Redfin - Why an employee chose Redfin

Redfin Launches Industry's First Online Home-Selling Service

Redfin Blog Post about testifying in front of Congress