The first thing you should do is determine why it has taken so long to list your property. The listing process places demands on the agent, their company, the MLS, and the customer.
Have you done your part in a timely manner? Paperwork is essential in this process and without everything completed and signed, things just don't happen.
In this situation... with this amount of time and no listing, there is a serious "breakdown" somewhere. If you are not the direct reason for the delay, you might consider other options because this level of service is unacceptable, in any market.
I would seriously consider contacting this agent's broker to request an explanation.
Nearly 3 weeks and not on the MLS....something's seriously wrong.