The YES Network has provided the list and a pretty good summary of each player.
Perhaps for the exception of the backup catcher position, it is unlikely that any of these guys will make the 25-man roster in April when the team leaves Florida for the start of the regular season.
However -- outside of an injury or other unforeseen circumstances -- I don't think there is any question that Phil Hughes is going to see major-league action at some point during the 2007 campaign, whether it is before the All-Star Break or after.