Why are house prices not collapsing?

The BBC news website published an interesting article today about house prices (http://www.bbc.co.uk/news/business-14020457).  This has made me think a little about what exactly is going on in the property market, and why, amid perpetual warnings of collapse, property prices have remained stable.  The article hints at various possibilities, but to me it seems clear that while the prices remain stable the depth of the market has collapsed considerably.  Many of those who would like to sell cannot because their current property value will not cover their existing mortgage, or cannot get a mortgage on a new property.  Similarly many would be buyers cannot obtain funding for their purchase.  What we are left with then is the tips of two ice-bergs.  On one hand the sellers, still with memories of 2007 and the values their properties reached, and not wanting to accept much below that now.  On the other hand the much reduced collection of buyers who can obtain funding, and are therefore willing to buy at current prices.  So, while the prices have remained stable it is at the cost of volume and market depth.  If you are lucky and you're prepared to wait you might sell your property at a good price, but should you need to sell in a hurry, don't expect a flurry of buyers at your door looking to view.