When DINOSAUR first opened as Countdown to Extinction the beginning and end of the time travel sequences featured rectangular lasers. These lasers have either not worked for several years, and there were reports that they were actually removed from the attraction.
It seems that a new laser/strobe/vortex effect has been installed at the beginning and end of the attraction. Initial reports include this video on Vine courtesy of TouringPlans.com as well additional reports on WDWMagic.com on May 17th. On May 21st, WDWNT.com posted the below video to their YouTube account showcasing the new effects at both the beginning and end of the attraction.