Not so much studies but leaks like this definitely push things forward. Every site breach that discloses the password database is a godsend for the crackers.
Think the RockYou hack was one of the 1st and biggest and exposed millions of passwords. Until then password crackers had little choice to brute force the hashes (try millions of guesses until one matches) or in the past pre-computed tables known as rainbow tables would be used but they are pretty useless today. The rockyou list gave a massive insight into the passwords people use. It also gave them what crackers call a “wordlist”. Now instead of brute force, you can load your wordlist into your cracking software and hashing your previously recovered passwords against the hashes you want to crack you’ll find massive amounts of passwords common to both sites and this makes cracking much more efficient. Every time more passwords are stolen and cracked, the wordlists get longer and longer and also info on how people choose passwords becomes apparent giving crackers another angle to throw at cracking.
