I've been to cosmo and its clubs a few times this year but actually stayed here for the first time a few weeks ago!
It's VERY pretty and VERY extravagant. i don't think any expenses were spared in making the cosmopolitan and you tell. the lobby area has really cool flat screen digital things that change wall paper and tons of mirrors to keep you entertained when waiting to check in (which took forever). i don't gamble but i think the casino area is really big because it takes forever to walk from the east to west side elevators!
rooms are nice too! contemporary furniture, lots of mirrors, and pretty big bathrooms. if you want a view of the bellagio fountains, you wanna request the east tower but the west tower is closer to valet and lobby. if you are coming with a group, you DEF need to request the same tower because it's SUPER confusing to go from tower to tower!
lots of places to eat and grab snacks at cosmo too! marquee day and nightclub get it's own review but very convenient how "one of the hottest clubs" in vegas is right downstairs :)
great location, gorgeous property and really enjoyed my stay.