Thanks to some additional publicity from fans of Ingrid Michaelson and Band of Horses, Round 4 was an incredible success with over twice as many votes as the previous rounds. Many thanks to those of you who voted; especially to the ones who took the time to comment on their picks. Thankfully for me, I didn't have any impossible decisions to make this round because there were no ties. Without further ado, here are the results as decided by you:

Avenged Sevenfold vs. LCD Soundsystem
Drew, a huge fan of metal and one of the few to have voted in every round, mentioned he felt A7X may be coming to the end of their run in this tournament. However, his vote, combined with many others, was enough to sneak A7X past LCD Soundsystem with 56% of the vote. The last hope for fans of electronic music is now gone. Metal fans, your hopes remain in-tact, but the field only gets harder from this point on.
WINNER: Avenged Sevenfold

Audioslave vs. The Black Keys
Although Audioslave has crushed each of the opponents they have faced thus far, their road ends here. Perhaps if Audioslave had allowed their music to be used in oh...27 more commercials, they would be on par with The Black Keys in terms of familiarity, but having already disbanded, it's not surprising The Black Keys, with their seemingly endless supply of television spots, were able to keep pressing forward in this tournament.
WINNER: The Black Keys

Band of Horses vs. The Decemberists
The Decemberists took a huge early lead, but a single post on http://www.odetoboh.net/ set their hopes to rest. As soon as Band of Horses fans were made aware their favorite music was in danger of falling to The Decemberists, they rallied the troops and settled the score. The result was Band of Horses taking 60% of the overall vote and moving on to the Euphonious Eight.
WINNER: Band of Horses

The Postal Service vs. Mumford & Sons
The Postal Service has been one of the great stories of this tournament so far. With only one album, released back in 2003, The Postal Service's music stands the test of time and not only earned a spot in the tournament, but managed to take out the immensely popular Vampire Weekend and the even more popular Strokes. However, after making waves in both the US and the UK, Mumford & Sons are the type of band no one wants to see on their schedule in this tournament. With 60% of the vote, Mumford & Sons moves on to face Band of Horses.
WINNER: Mumford & Sons

Ingrid Michaelson vs. Sara Bareilles
Even friends fight sometimes. Although Sara Bareilles apparently earned the "metal vote," there were some, like Susan, that didn't want to choose between these two artists since they are both phenomenal musicians and songwriters. Like all tournaments, however, some one has to lose and in this case, that person is Sara Bareilles. Ingrid fans, you did it. Now don't let this victory go to your head. Keep those votes coming for the next round.
WINNER: Ingrid Michaelson

Lady Gaga vs. Alexi Murdoch
As big a fan I am of Alexi Murdoch's music, I have a feeling (as do many others) that this contest was really more a choice between Lady Gaga and Not Lady Gaga. With 53% of the vote going to Lady Gaga, pop music's newest queen moves on. This was easily the closest contest of the round. Lady Gaga moves on to face Ingrid Michaelson to determine the winner of the "Solo Artist" region. Should be an interesting match.
WINNER: Lady Gaga

Arcade Fire vs. Franz Ferdinand
This was a lot closer than I thought it would be. The bands match up well, but there is a glaring difference between the two in terms of both publicity and critical acclaim. Arcade Fire, indie darling gone international sensation, eventually pulled off the win with only 57% of the vote. Does this spell trouble for them in the rounds ahead? Only time will tell.
WINNER: Arcade Fire

Kings of Leon vs. The Killers
Bobby pointed out that Kings of Leon should definitely have more votes, and would if this tournament were better known to European fans. While I agree with him on both counts, Kings of Leon's latest album was a disappointment to many and may have been a deciding factor for fans that were on the fence when deciding the outcome of this contest. In the end, The Killers managed to sneak by with 56% of the vote.
WINNER: The Killers

Many thanks to everyone, once again, for voting. With only eight bands left, the decisions may be getting harder, but the results get more interesting. Round 5, "The Euphonious Eight" will be posted on Monday.