Having bought and played Lords of Waterdeep for the first time yesterday, I found it to be both a success and a disappointment. It's my first physical worker placement game, though I enjoy Caylus iOS, and I've been reading up on Agricola and a couple of others for a while. I feel like I have fully grasped Agricola, but I bought LoW as a gateway game not only for me, but for my friends.
Everyone I play boardgames with is at my level (noobs, basically) so if I want to play something like Agricola, I have to make sure they're ready too (and they're not the type to watch 30 minute instruction videos and go through PDF files of the rules). In that regard, LoW was a success. They all found it simple and they enjoyed it a great deal. It really helps that the components, card stock aside, are really nice. It probably has the best presentation out of all of the games I own and there are a lot of really nice touches that they really didn't have to do, but they pushed the boat out and it's stronger as a result. None of us have had anything to do with D&D before, so we didn't just like it for that reason.
Personally, I found it a bit boring. Perhaps it was because I was far in the lead throughout, but from my limited research of worker placement games and my time with Caylus iOS, I find appeal in the struggle and the tough, increasingly limited decisions you have to make. With LoW I never felt that struggle. The worst situation I found myself in was "Oh no, there's only one spot to get a white cube and someone is already there. Now I have to wait one round" but that didn't put me in a pickle because there was always other colours to pick up that I knew would be useful in the near future based on the visible quest I know I can just pick up.
So basically, I bought it as a gateway game, but I found it to be too simple. They all managed to pick it up faster than even Catan and 7 Wonders (heck my best friend looked more confused when I first told him the rules for Ticket To Ride). Perhaps I just had a fortunately (or unfortunately) easy first game and I'll find more depth in future. Or maybe I should have went with Stone Age. Either way, it wasn't terrible and I don't regret it. I'm always happy to have more games that I can easily get all of my friends to play.