I am also a new Diamond member and to be honest, I cannot say that I am blown away by the benefits. I have had 20 stays in the last 8 months mostly in North America.
Most properties I welcomed me as a Diamond, but rarely upgraded to a suite of any merit. Ocassionally an amenity gift like a tin of nuts with water. In Vancouver Burnaby Hilton, I was told I could not use the Lounge but they check in guy said he would overrule it. Wow, thanks!
In comparison to SPG Plat, there is a world of difference and not for the better.