Originally Posted by dgreen12

• The maximum elite night credits allowable to be issued
  from Chase to your Marriott Rewards member number per year
  is 15.
• [T]he offer to receive a Free Night Stay enrollment certificate is valid
  only for first-time Marriott Rewards Visa Cardmembers.
  Previous or existing Cardmembers do not qualify.
• Enrollment points are valid for first time product type
  only. For example; If you have received enrollment points
  on a previous Marriott Rewards Premier account, and open
  an additional Premier account enrollment points will not
  be issued. If you are opening an account type that you
  have not have previously had, such as a Business Premier
  account, the account will qualify for enrollment points
  only.

So, if you already have a personal Marriott Rewards Premier Visa Signature card, you won't receive an extra 15 nights for getting the business card (only one 15 nights per Marriott Rewards account), you won't receive the Free Night Stay certificate (not a first-time cardmember), but you would receive the 50k bonus enrollment points (since it's the first Business Premier account).

Pass.