Site hasn't striked since the late '80's. Near misses, but cooler heads seem to prevail in what seems to be a once a half decade game of chicken.
OTOH, Big Oil has saw some unprecedented hard times in the last year, and the likes XOM, CVX, et. al. might not be in such a good position for concessions. At this exact moment, I give the odds of a strike at about 30-40%