The property market in the UK has been booming over the last few years, with 33% of houses selling within 3 weeks, and 60% in less than 10 weeks. However, the market began to slow down in 2004, and by the end of the year, the number of unsold properties was the highest it has been for four years.
Before putting your house up for sale, you should investigate the state of the property market, as it isn't advisable to sell during a property slump, unless you absolutely have to. It may be more prudent to let your home long-term and wait until the market has recovered.