Map Popularity - BLAST Major vs. MM
Mirage and Inferno are the pros most-played maps in the Major so far, but not my nearly the margin that these maps are in MM.
Pros are more willing to learn new maps than the MM playerbase as a whole, so the percentage of games played is more even across the board in the BLAST Major.
Map Sidedness
We also compared which maps were CT-Sided or T-Sided:
Inferno, a famously CT-Sided map during the Astralis era, has flipped to be T-Sided so far in the current major. The biggest disparity between MM and the Major comes on Overpass, where Pros have been winning 11% more rounds on CT than casual players.
The sample sizes for the Major are on the order of 100 maps, whereas 350k MM demos were processed. This could contribute to the fact that the MM distribution is flatter overall, whereas the Pro distribution shows more variability from map to map.