From everything I have read, cinesphere will NOT be playing on May 28th. Here is the schedule:
http://www.universalorlando.com/shows/blue-man-group/showtimes.html
Universal 360 Cinesphere Spectacular:
EVENT DATES
April 5 - April 10, 2009
April 12 - April 17, 2009
July 3 - August 15, 2009
SHOW TIMES
Show time will be at 9:00pm nightly on the dates specified above.
Wrap up your day at Universal Studios with the big Hollywood finish of Universal 360A Cinesphere Spectacular.
Through the unique "Cinesphere" technology you'll experience the sights and sounds of some of Hollywood's biggest films projected onto huge spheres in the Universal Studios lagoon, plus one of the largest laser displays in Florida, dazzling pyrotechnics and more.
It's the most explosive, jaw-dropping cinematic adventure you've ever seen!
Edited to add: Now I know what you did. You clicked on the date under Blue Man Group. It is on the same page but the Cinesphere schedule is at the bottom of the webpage.