I have had a Marriott business VISA card since 2007. Today I received an e-mail offer to upgrade to business Premier VISA card which I immediately jumped on. While the annual fee jumps from $45 to $99 I now get: Annual free night up to Cat 5, 5 points/$ at Marriott properties, 2 points/$ at office supply/internet/cable/phone services plus restaurants/car rentals and airlines. This will eliminate the need to use my personal Marriott VISA when paying for business hotel usage. There are some other bennies, but minor compared to the above. In was not aware before this that there was a business Premier card, or I would have requested it. The free cat 5 night more than covers the extra $54/year.
The old one was 10 nights, but if I remember correctly, they do not stack the nights from multiple cards. They just use the personal card. I wish they would stack the nights, because I have a second Marriott business card that I would also convert to Premier. That would give me 45 nights/year if stacked!