One of the more contentious points among Dota 2 fans is whether some form of a public MMR should be associated with each player. Unlike another often argued feature the surrender option however, very soon it looks like MMR will become a reality.
Popular stat tracking site Dotabuff.com will soon be introducing what they are calling a "DBR" or Dotabuff Rating to every profile. While not a mirror to the internal rankings used by Valve (which are likely unknown at this moment), a player's DBR will according to the site be an accurate representation of what percentage of the player base you are ranked into. In addition to this knowledge they will also assign a bracket to each player depending on that ranking.
While some view this feature as a net positive (or so the poll results say), many detractors worry that the pubic rankings will lead to pre-game analysis of your team mates and potential flaming towards players matched against higher skilled players. Essentially the worry is that it will further perpetuate what is already seen as a hostile environment in comparison to other games, making the game less friendly all around.
Regardless of how you feel, public MMR looks to be a reality that we're unlikely to avoid. We should know more once the rankings go live this Friday.
Source: Dotabuff Rating (DBR) Poll