Hey, hey, watch it, now! <g>
Actually downtown Memphis has changed radically in the last few years. The building of the downtown AAA baseball stadium, kind of a miniature in the style of the one in Baltimore, then the Peabody Place development and most recently the FedEx Forum, where the NBA Grizzlies play. Beale Street and the downtown shops and restaurants are all really doing well. There's also some nice stuff going on over near the Civil Right Museum (the old Loraine Motel where Dr. King was killed). That area is becoming very much an artist's colony and some interesting shops and restaurants are showing up there. It's still not a great area, but it's better than it used to be.
As to Platium Plus, I remember when they opened that place up. There were picketers complaining that it would "drive down the quality of the neighberhood." I laughed out loud. If you know the area then you know that the neighberhood is full of car dealers. The "gentleman's club" would raise the quality and the morals of the neighberhood.
I can deal with Collierville. Germantown and even the Southwind area is slipping. The places you mention are fine during the day, but you slip a block off of Poplar or off Beale and you may end up dead. Sorry. The place is run by King Willie and is about as well run as DC. I couldn't take it anymore and had to leave. Good luck and be careful if you live there.