Two items in The Christian Science Monitor (here and here) directly address the potential for NATO involvement with the latter of the two articles noteworthy in its quoting NATO's Secretary-General, "'We have all necessary plans in place to protect and defend Turkey if necessary,' said NATO Secretary-General Anders Fogh Rasmussen."
The Telegraph and The Atlantic both have good overview stories about the potential for war between Turkey and Syria, noting the problems caused by the flood of refugees into Turkey (also here), the support Turkey is providing the rebels (angering Syria) and Syria is providing the Kurds (angering Turkey), and the pressure likely being felt by both governments to not be seen as 'backing down' in the face of the other's provocative actions. 'National pride' can be a powerful motivator for starting wars that no one actually wants to happen.
Then there is this complicating piece about Turkey taking exception to Russia allegedly sending advisors and equipment to Syria through Turkish airspace.
Hmmm...a tangle of alliances, national pride, ethnic rivalries, insurgencies, great power competitions, tottering regimes attempting to maintain power at all costs. Reminds me of the conditions leading to World War I. How interesting...