There are sources out there, suggesting a further weakening of the market.
Just read the link you posted but cannot say that just because there is less demand for properties already on the market, that this is a reason for a decline in prices. 95% of the properties advertised are rubbish, overpriced and would find it difficult to sell at even cheap prices.
When I first came to Poland in 2002, I was going to build my own house (being a builder for 30 years it would be easy) but continually got messed around when trying to buy a decent plot of land, I would agree a price for the land, get planning permission and then the landowner wanted more money because his friends and family thought it was worth more. (This happened a couple of times and wasted months of my time)
Anyway, after 2 years of this crap, I started looking for a house to buy as I was not getting any younger. I started looking in earnest for a place for a further two years but could not find anything that I liked, then I found out a new baby was on the way and really panicked, had to look further out of the town than I had before but managed to find my semi-perfect house by accident, there was a "For Sale" sign on the gate. The couple who lived in/built the house had spent 3 years in the UK when they graduated from university, so, the build was more or less of an English design and quality.
When somebody buys a flat/apartment, they know that all the rest of the building is roughly the same, quality wise. An individual house is something different, it has to feel right, it has to meet the criteria for growing kids and for when you get older and cannot manage the stairs etc. A house is a long term project, even the way you landscape the gardens is a statement of your own personality and is carried out over many years. I know in my heart that if I had bought any of the houses that I had previously viewed, I would have ended up demolishing them and starting from scratch as I would never have been happy.
Sorry this was a bit long but wanted you to know from a personal experience how hard it is to find the right place.