Answer
Acts 1 refers to these people as "the brethren" (Acts 1:15), which is Luke's (the author of Acts) normal phrase for believers, and contains no account of their coversion while in the upper room. In Acts 2, all these people received the power of the Holy Spirit to be witnesses to the gospel. Since we have no account of their conversions prior to or at the upper room or Pentecost, the most logical inference to draw from this is that they were already saved.
Answer by Ra McLaughlin
Ra McLaughlin is Vice President of Finance and Administration at Third Millennium Ministries.