TheStreet's Jim Cramer is astonished that David Marcus is going to Facebook and leaving Paypal. Cramer says PayPal is why investors want to own eBbay and Marcus has always been known as the man behind the scenes who made PayPal worth as much as it is. When Marcus leaves, it becomes a situation similar to Beats, minus the three billion it took to get Dr. Dre and Iovine. Cramer says Facebook gets the guy who is "Mr. Monetization." Cramer says Marcus is the master at finding a way to make people pay for services without them feeling bad about it. That is exactly what Facebook's whole issue has been: find a way to get users to pay without user experience being compromised. Cramer says it is a brilliant move by Facebook. Cramer warns investors to be careful of the daily sellers on Facebook at midday.