Question Pack 1 has about 400 practice questions. Some of these questions have been published in other products in the (rather distant) past, but those questions were removed from the other products and moved to Question Pack.
Exam Pack 1 has 2 practice CATs. It's unclear whether some of these questions might be old ones that were previously published in the distant past (they just launced this a few weeks ago). The questions don't overlap with current products. I asked GMAC about this recently and they told me:
There is no overlap between any questions in the GMATPrep® software suite and those in the Guides or any other GMAC product.