It's easy for all of us to sit here and second guess your agent who is probably sitting at home right now trying to figure out other marketing strategies to get buyers into your home. Sit down with your agent, talk to him or her. Your agent is most likely as frustrated as you are. But that doesn't mean that they don't care and want to get your home sold. Keep in mind that your agent doesn't see a penny until your home is sold and has probably spent quite a bit of his or her own time and money marketing your home, gas money getting to and from your home to talk to you, do open houses, etc, and they won't get paid until your home is sold and closes and if you decide to relist with someone else, they won't get paid at all, regardless of how much money and time they have spent on your listing. Sit and talk to them about why your home hasn't sold, review the feedback you've gotten from showing agents and the agent open house, but also talk about the absorption rate for your area.
In the 63301 area since March 1st of 2008 there have been 525 homes on the market , ranging in price from $20,000 (sold the day it went on the market for $30,000) to 1 listed at $1,575,000 that sold for $469,990 in 703 days (and yes that is correct). 51 listings sold in the first 30 days they went on the market, 30 sold in the next month, 20 in the 3rd month, 17 in the 4th month, 21 after that out of the 139 that sold out of the 525 that were on the market. Now in the past 4 months, 41 homes went pending and 139 closed, that's 180 homes, or 45 a month. There's 239 active listings left in your zip code that you are competing against, which is over a 5 month supply of homes on the market. that you need to be better than in order to get the contract (now since I don't know your price point or your exact location and school district, this is obviously very broad, with that data - which your agent has - the numbers become more realistic for your situation, but you may still be looking at a 5 month supply of homes on the market that you are competing against!)
Go visit the homes that have sold and the ones that you are in competition against now. If there are things that you need to do to your home to improve it's position in the market do it. Consider hiring a stager who will help you to either stage your home with your own belongings and a few accessories that the stager will bring in, or put your belongings in storage and use the stagers stuff - it can make a huge difference (your house has to have personality and charm on it's own, but it can't be so full of your personality that the buyers can't see the house for your stuff). It's been 4 months, take a look at your home and see if you need to "freshen up" anything that you took care of 4 months ago, but in living in your home has gotten a bit "worn". Do the minor repairs - buyers look at minor repairs and immediately think that if those need to be done that major things need to be done. replace flooring and paint if needed. And if you have the misfortune to be in a bad location, have a bad yard or one of the other attributes that you can't fix, then adjust your price point because that's the only fix you can do in this market that will really work on top of making sure that everything else shines.
I've been showing in that area a lot recently and my buyers probably saw 60 homes. Some were great, some were so bland and blank that they had absolutely nothing distinguishing about them, they were just a house. Some had great yards, some had finished basements, some had walk out basements, some obviously needed work, some the buyers felt cheated because the MLS description really didn't match the house (calling an open loft area a bedroom for example), some had great sunporches, others wonderful decks or patios. Some were well painted and staged, others obviously had elderly home owners in them from the decor, some backed to very busy roads, some backed to common ground. My clients looked at a lot of homes, and chose one that had a finished basement but it wasn't a walk out but had a full bath, had a nice yard, and had a nice flow to it. The flooring wasn't as fancy as some (more vinyl instead of tile) It wasn't the fanciest that they saw, or the most expensive or the least expensive, it was on the market less than 2 weeks when we made the offer, and it was in excellent condition (the building inspector found only minor things).
The last one I listed in that area went under contract in a week, but they did what I told them to do to fix it up to sell it quickly.
Listen to your agent - ask them what you need to do, then do it. Talk to your agent.ask them what they would suggest to "freshen up" your marketing and get more buyers to your home.