The big issue is with a debit card, it is holding your actual cash. On a credit card, it's just your credit line.
A hold will be cleared with a charge using the authorization code.
Long story short, this will cause some teething issues for guests that prefer their Debit card instead of a credit card.
Credit card users won't notice this change.
It only really becomes an issue if someone uses a debit card at check in, but intends to use a different card at check out. The authorization won't clear, then it will hold the funds on the debit card up to 30 days(as of 5 years ago that was the case, i'm out of the biz now) and 60 days for canadian debit cards. It's a complete pain in the keester if you happen to be working in the hotel/resorts accounting department and have to deal with it. Less of problem with small community banks, but a huge pain with big banks like chase etc.