So, why has The Bataclan specifically been targeted?
Below is an explanation from the weekly french magazine Le Point: http://www.lepoint.fr/societe/le-bataclan-une-cible-regulierement-visee-14-11-2015-1981544_23.php:
We had a planned attack against the Bataclan because owners are Jews." This sentence, chilling with regard to the taking of hostages and the carnage that would have made this Friday, "a hundred dead" according to police sources, was delivered to the offices of the DCRI, in February 2011. The French services while questioning Member of "Jaish al-Islam," the Army of Islam, suspected of the attack that killed a French student in Cairo in February 2009. They planified an attack in France and was therefore targeted the famous Parisian theater.
In 2007 and 2008, the Bataclan was already under the threat of more or less radical groups. At issue: holding regular conferences and galas of Jewish organizations, including the "Magav", a border guard unit depending on the policy of Israel. In December 2008, whereas the Israeli military operation takes place in the Gaza Strip, the threats around the Bataclan are more accurate. On the web, a video showing a group of a dozen young, face hidden by keffiyehs, threatening officials Bataclan about the organization's annual gala Magav. At the time, Le Parisien devotes an article without this handful of activists to be truly identified. In the process, the annual meeting will be postponed.
Since then, whenever a Jewish organization meets at Bataclan, many hostile comments flourish on the web. Yet in recent years, they seemed to have faded. Nevertheless, the Israeli press recalled that the rock band Eagles of Death that occurred Friday 13 evening, had toured Israel. The group was then faced more calls for a boycott, which had not prevented him from producing it.