the short answer: match... against is WAY powerful and has a zillion options, where like's '%' wildcard character is just a shortcut wildcard. which, incidentally, often works great. match...against is really a big thing ;-) check out the mysql docs for full details:
http://www.mysql.com/doc/en/Fulltext_Search.html
p.s. to moderators this whole thread may go better in the db topic, fyi.
best
eric