It's all about money.
Just read that article a few days ago:

Business-minded JON BON JOVI is waiting to see how the U.S. economy shapes up this summer (0 before deciding whether to schedule a tour in the country. Bon Jovi kicked off their latest tour in Nebraska on Monday night (18Feb0 but a second leg will depend on state of the economy. The group will be touring Europe in May and June (0 and will wait before announcing more American dates. Bon Jovi admits he has a string of baseball stadiums on hold, but the band might not head home. He says, "We (could) stay in Europe because of the state of the economy. All the arena shows (we're playing) are sold out, but the July dates, I'm not sure where the economy's going to be, so I don't know yet
http://www.contactmusic.com/news.nsf...20turn_1060032