Just read on Glaxo thread about 15k retention bonus.... whats fair is fair? We are also riding this merger roller coaster ride and 15k sounds good for NVS too!
The general trend in reps per rev$ is up anyway so if leave prior to the addition of their reps you just save them the hassle and costs of laying you off later anyway. Novartis bought GSK Oncology with reductions in total reps in mind.