Apparently, XIN keeps the worst secrets when it announces them in the press release. First, the NYC purchase was well circulated in this board couple of days before the PR. That' s near when the recent rally began. Then, again, couple of days before the Beijing land purchase PR, the news was already posted here.
Now, I understand why good news related to XIN only helps the stock go up a day or two. Simply, many people with insider information buy in advance, and then dump the shares during the announcement day. This is one of the reasons that I don't like Chinese stocks like XIN. The company like many other Chinese companies has very pool compliance management. Many investors are hurt by such activities.
In this case, short-term traders without insider information will be hurt most by counterparts who possess insider information. Long-term investors may be relatively well positioned. However, given the level of insider information leaked into the market, it is hard to believe XIN is still significantly undervalued.