I just read an interview with a Syrian journalist (in Hebrew [link|http://www.ynet.co.il/articles/0,7340,L-3282166,00.html|here]) where he states that the atmosphere in Syria is like right before a war. Syrian TV for the first time since the 80's is showing military marches and playing military music. The journalist commented that everyone in Syria knows that Israel is preparing for war with Syria.
I find it hard to believe that Syria will attack Israel, but you never know. They may think that Israel is preoccupied in Lebanon and Gaza and they may start believing the Arab newspapers that the IDF is no longer that strong and try to take back the Golan Heights.
Israel has no plans to attack Syria. However, if Syria attackas Israel, Iran who recently signed a defense treaty with Syria will be dragged in as well. The US recently promised to help defend Israel from Iran, and therefore a Syrian attack could very easily lead to the US fighting with Syria and Iran as well.