First Deposit Bonus:

     PlayersOnly offers a 100% first deposit bonus up
    to 650$.  In addition to this they add a 10%
    instant deposit bonus.  Taken together this puts
    PlayersOnly at the top of the first deposit bonus
    list.  They are the site offering an instant bonus
    right now, as far as I know.  The extra 10% that
    you get should make clearing the 100% bonus
    a no brainer.  The 100% bonus is cleared by
    earning Player Points at real cash game or
    tournament play.

    Loyalty Program:

     Since PlayersOnly is on the Cake Poker Network
    they use a program similar to Cake's, which includes
    Gold Chips and Gold Cards.  Gold Chips consitute
    the heart of the program-these are earned by
    earning FPP's, Frequently Player Points, which
    automatically turn into Gold Chip when you've
    earned a certain amount.  Gold Chips can then be
    used for tournament entries or to buy merchandise
    from the PlayersOnly store, which includes a wide
    array of electronics, games, media, and poker
    supplies. 
       Gold Cards are collected by playing at real money
    tables, and are given out on a more or less random
    basis, although playing at larger blinds will get you
    more Gold Cards.  Gold Cards can be used to enter
    lotteries for tournament entries, or for their yearly
    contest which awards 52,000$ for the first person
    to complete a full deck, or the largest collection if a
    full deck has not been completed.