Fast Company has a good article laying out the state of events regarding the Internet in Syria.
Here is the short version. Syria has changed tactics from keeping the Internet available but highly monitored and surveilled, to turning off apparently absolutely all Internet connectivity within the country.
Syria was unique in its cyber response to their Arab Spring uprisings. Rather than lock down the Internet, they actually un-blocked some popular social media sites. They did this because of the incredible surveillance capabilities this makes possible. Business Week has a nice story on this aspect.
The change of face would seem to have a few possible reasons.
1) Dissident tactics like encryption are making the surveillance less effective.
2) The damage from dissident publishing is greater than the value of the intelligence.
3) The Syrian government is about to do something really nasty and they want to make it very hard to report about it.
We shall see. The fact that the Syrian government appears to have turned off even its own Internet access suggests that they are worried about any leaks through the wall, which makes reason 3 seem more probable.