For more information I recommend the books The Caucasus: An Introduction and The Ghost of Freedom: A History of the Caucasus. Avoid "Chechen Jihad" and its many non-cited lies like the plague.
Click to enlarge. Ethnic Russian in red, ethnic Muslim in green, ethnic Christian in blue, ethnic Buddhist in yellow
While most people are focusing on the War on Terrorism in Afghanistan and Pakistan, things are picking up again on the Southern Russia front. Russia is quadrupling its forces there after a failed experiment of relying on local, pro-Russian militias (thugs) against local, anti-Russian militias (thugs) who fight along side foreign Islamic radicals. (2013 note: This has seemed to work as overall violence levels have been held in check. However, militant Islamists from this region are active fighting in Syria, Afghanistan, and elsewhere. Eventually they will "come home".)
Few people fail to realize just how ethnically fractured Southern Russia is and how this has overflowed into international violence. Not all areas have been trouble spots. For instance Buddhist Kalmyks have gotten along fine with their Russian neighbors and the same goes Adygeya and Russians. However, even before the collapse of the Soviet Union this has been a trouble spot.
Trouble Spots to Watch: (2013 note: Not so much. Ethnic and Cultural Russians in Ukraine have won back power in the country and lines of control in Georgia seem set).