5 minutes of online research reveal that LiveNation Denver just had all their top staff headhunted away by Regal Promotions group, and LiveNation is ending their relationship with Ticketmaster in 2008. If you want to post a message on their discussion board on Yahoo discussing these items in the context of their inability to maintain venue commitments in the Denver market, you'll hit them where it hurts the most.
http://messages.finance.yahoo.com/mb/LYV