Tips for mousekeeping and bellmen. It is usually $1/person/day for the mousekeeper. I take a new envelope for each day in case it is a different mousekeeper.
I am not sure what hotels you will be staying at, if there will be bellmen, but if so, plan at least $1/bag.
If you plan to do anything more than counter service at WDW, I feel $60/day is too little.
Does your hotel provide breakfast? If not, plan $15.00 for breakfast. Counter service will be $15.00 - $20.00 for lunch. This leaves $25 - $30 for dinner each day. Depending on what you plan to do, counter service in the park, sit down in the parks, or eat outside the parks. Counter service will be fine for that amount. There isn't anyway to eat a sit down dinner in the parks for that amount. If you plan to eat elsewhere, it can easily be done. If you are going to buy groceries for b-fast in your room, or your b-fast is provided, then that helps free up $$ for other meals. It all depends on where you are staying and what your plans are. If you go to allearsnet.com, Deb has menus from the restaurants at WDW. It could help you decide what is a reasonable budget.
Additionally, there are vouchers that are discussed here, that show how two of you could share a $30.00 for a big lunch or even dinner at RFC at AK.
Do you plan to go clubbing at night? If so, that can be quite expensive.
Hope these thoughts help.