Pros
Depending on the location you're in within the company, opportunities and recognition can be stellar. The company moves at an incredible pace in some segments and has tons of new, emerging chalenges. Never gets boring.
Cons
Alignment within Kenexa, that grew as much through acqusitions as it did organically, is very poor. Different business units often operate completely differently and have entirely different report-to chains, making cohesion/cooperation and conflict resolution challenging. Kenexa has never invested heavily on internal software development R&D, generally looking to make the sale at any cost. This leads to a lot of skeletons in the closet. If you're in the wrong place in the org, there can be poison management chains. Be aware of the culture of the specific unit you'd be joining.