Investors have been agitating for this split for a very long time now. Because they feel that eBay is holding PayPal back. PayPal has been providing most of the earnings growth over the last several years and financial stocks have done much better than eBay which is why investors feel they would be better off if the companies were split.
Also PayPal doesn't want any alternative money processors like 2Checkout, Google Wallet, WePay, Authorize.Net, Alipay, Apple Pay, Intuit, ProPay, Click2Sell, Dwolla, Braintree, ClickBank, Stripe, Gate2Shop, or Perfect Money gaining any ground on PayPal.
I don't see many changes happening eBay and PayPal will continue to cooperate and will more than likely still share data.
You have to remember that the only thing we can all count on is the game will constantly change. Those of us who were selling online in 2010 and before can tell you that selling today is quite different. Nobody here knows exactly what the future will be like but I can tell you this it will be different than it is today.