a farewell expression, derived from "see you later" or simply "later" or "late". some moron probably from camarillo, california thought adding an 's' would be funny. but it's not.
A combination of two proper phrases, "As of today," and "Lately," meaning an event which recently happened or has been happening repeatedly. Current indifference to butchered English has made its use more popular than the correct phrases, elevating it to more innocuous than similar travesties "These ones" and "On accident."