Bonus values are a new thing, having been agreed to by the MLB Players Union in the newest CBA. The penalties can be harsh, with one consequence being fined and losing next year's 1st round draft slot if a team goes over their total allotment assigned to their picks in the first ten rounds. Any pick after the 10th round has a cap of $100,000. Anything over that will be counted towards the money in the first ten rounds. Last year some teams got creative by drafting hard to sign, high upside high school players in the first 5 or so rounds then drafting college seniors who'd sign way below slot in rounds 6-10.
A's First 10 rounds (Round-Pick #)
Here are some local names to watch for early in this year's draft: Matt Krook (St. Ignatius), Mark Appel/Austin Wilson (Stanford), Andrew Knapp (Cal), Jordan Paroubeck (Serra HS), and Alex Balog (USF).
For a more complete list of California draft eligible players, click here: http://www.baseballamerica.com/draft/2013-state-draft-report-california/