Publishers are paid via PayPal or International Wire / Bank Transfer within 60 days after the end of the month. That means that you'll receive your earnings from February 2012 at the end of April 2012.
Publisher earnings over/equal to $50 will be made to your account. If you do not reach this amount in any given month, your balance will simply be carried over to the next month(s).
To check out your earnings, login to your SlideME account first and then visit http://ads.slideme.org to access the Ads! portal.
Wanted to know more, check out Introducing: SlideME Ads