2

Ancient

Ancient is back in the Active Duty Map Pool. Same as the end of CS:GO. Other than some visual aspects and Cubby that is smaller, there are no real changes.

Anubis

Same minimal changes. Visual appearance is improved, water looks pretty, but other than that no real changes

Inferno

The whole feel of inferno changed. Map feels bigger, because a lot of stuff got wider. A retake got more doable because of pit molly from appartements. And on B players can now plant in the water. (And also, the fruits can be shot)

Mirage

Mirage just got a lot brighter, making previous dark and hard to spot corners a lot better. skybox changes to make smokes from ct to mid a lot easier and the floor in palace is now super shiny

Nuke

Valve considers the cs2 version of Nuke to be an upgrade rather than an overhaul. The biggest change you'll notice is the shadow, where even indoors there's places with shadow advantage.

Overpass

The changes in Overpass are mostly graphical as well, with some minor gameplay changes. Long self boost is now easier, because of the propane tank. A little window was added in toilets towards long.

Vertigo

Vertigo's changes are mostly visually.