It says right on that page that the hotel will continue to participate in SPG, so yes, you are entitled to your platinum benefits.

Basically, the hotel is being de-branded as a W. I guess the mostly suites concept doesn't really fit with the W brand, yet we still have the W Silicon Valley in Newark, CA? I've never stayed at this property, maybe the master thread for it will be more revealing as to why it's being de-branded.

There are a few others, the biggest one is the Manhattan Hotel and Towers, which was de-branded from Sheraton last year because it wasn't up to Sheraton's standards, and Sheraton went through a fairly extensive brand renovation last year.

I guess if you really want to know how many, you can look through the properties listed in the FAQ?

-David