It really depends on what you're willing to do and what your budget for hotel rooms is set at. My first stay was at
MGM Grand, and ever since I've been partial towards staying on the south end of the strip. Even though, during that stay, City Center AND
Planet Hollywood were both under construction during that trip. My next trip was that same year for a conference at
Mandalay Bay so we stayed there. I'm a walker, so I don't mind being deep south. The farthest north I've stayed was
Bellagio, and I must say, that was the best in terms of being conveniently located to everything. That said, most of my gambling is done on the south end of the strip, so that could also be why I prefer the south end.
So, if you like gambling on the north end of the strip, then you should look for properties on the north to stay at. In 2009 we stayed at
NYNY but my favorite slots (Star Wars) were only found at
Venetian and
Palazzo so we had to do a lot of walking. Worth it, but we probably did a lot less gambling as a result. So, location should be based on where you want to spend most of your time.