Once your results are available, you'll be able to go into your personal page at FTDNA and do a search for yDNA matches. You'll always see all of the other results in your surname - and at that time, you'll be able to select a preference that allows you to compare against all others of all surnames who opt in to the FTDNA internal comparison. (When your results are back, Worldfamilies.net will post them on your surname project’s Results page.)
You'll also be able to upload your results to Ysearch (FTDNA's public database - open to all) and see who you match there.
FTDNA will send you automated messages when you have a match (either with only your surname project members or to their internal "opted-in" database) - depending on your selection.
For more information on how to interpret your "matches" with other people, take a look here:
http://www.worldfamilies.net/faqs.html#match