Why does this app seem to block at line 42?

ITunesApp.scala

package org.satyagraga.dispatch.evaluation

import dispatch._, Defaults._
import org.json4s._
import org.json4s.native.JsonMethods._

case class ITune(trackId: Int, trackName: String)

object ITunesApp {

  private implicit val formats = org.json4s.DefaultFormats

  val itunesUrl = "http://itunes.apple.com/search?term=metallica"

  val itunesApi = url(itunesUrl)

  def callITunes(): Future[Either[Throwable, String]] = {
    println("callITunes - enter")
    val res = Http(itunesApi OK as.String).either
    println("callITunes - exit")
    res
  }

  def extractITunes(itunesJsonData: String): List[ITune] = {
    println("extractitunes - enter")
    val res = for (ituneJson <- (parse(itunesJsonData) \ "results").children)
      yield ituneJson.extract[ITune]
    println("extractitunes - exit: " + res)
    res
  }

  def fetchAllITunes(): Future[Either[Throwable, List[ITune]]] = {
    println("fetchAllitunes - enter")
    val req = callITunes()
    val res = req.map(resp =>
      {
        println("fetchAllitunes - callback - resp")
        val ituneData = resp match {
          case Left(throwable) => Left(throwable)
          case Right(itunesJsonData) => {
            println("fetchAllitunes - callback - itunesJsonData: " + itunesJsonData.take(100) + " ...")
            val itunes = extractITunes(itunesJsonData)
            println("fetchAllitunes - callback -itune list: " + itunes)
            Right(itunes)
          }
        }
        println("fetchAllitunes - callback - ituneData: " + ituneData)
        ituneData
      })
    println("fetchAllitunes - exit - res: " + res)
    res
  }

  println("fetching allITunes")
  val allITunes = fetchAllITunes().apply
  println("allITunes: " + allITunes)
  allITunes match {
    case Right(itunes) => println("itunes: " + itunes)
    case Left(throwable) => println("throwable: " + throwable)
  }
  println("allITunes: " + allITunes)

  def main(args: Array[String]) {
    println("Running...")
  }

}