While egold may certainly be very well known, they don't even have a fraction of the transaction volume or reserves as paypal -
e-gold Examiner
On the flip side, while I don't' have the raw numbers, I believe it's:
1 - PayPal
2 - Neteller
3 - CCBill
4 - 2Checkout
5 - Clickbank
This of course is in terms of third party billers.
But ultimately paypal accounts for all the others combined in transaction volume.