From the article it appears that the reported increases will be used until 2011 to determine taxes. Nowhere does it state the time period for the increases. As the valuations are good for 3 years, it's probable that the increases are for a 3 year period, 2005 until 2008.

From what Thai's have told me the property valuations are lower than the market values, but not by a lot.

Even if we each brought 40,000,000 THB into the economy we wouldn't even cause a ripple in the overall economy, although it might be cause for celebration for a village or extended family. There are so few of us we have very little impact on the economy. Tourists are another story.