Rian,
Thanks for the questions.
(1) MVP is a disorder of the connective tissue of the mitral valve, and thus is frequently seen to involve both the anterior and posterior leaflets.
(2) Close follow-up is the only way to know if you will need surgery. If your EF remains normal-high and the mitral regurgitation remains the same, then it is quite possible that you will not need surgery. Having regular follow-up, as your doctor recommended, is the key. It should be reassuring to you that he/she didn't think that you needed another echo for 2 years.
I've included a quote from the American College of Cardiology Guidelines on Valvular disease (http://www.acc.org/clinical/guidelines/valvular/jac5929fla16.htm#D):
"Reassurance is a major part of the management of patients with MVP, most of whom are asymptomatic or have no cardiac symptoms and lack a high-risk profile. These patients with mild or no symptoms and findings of milder forms of prolapse should be reassured of the benign prognosis. A normal lifestyle and regular exercise is encouraged."
Hope that helps.