What is vanguard?
Here is a rundown, or the basic idea, I think...
SoE had their hands in the EQ project with Verant before it was released and I believe something happened and SoE dropped out and left Verant hanging. Verant released EQ anyway and it was an instant success and SoE had to get back in their to get a piece of the pie. Eventually they decided to take a larger piece and the good guys at Verant said FU and left. This is why up to the Velious expansion the game was consistent and actually good for its time. From there the game took some strange twists because it wasn't the brians behind Verant designing the game anymore, and it's why to this day EQ has basically turned into a cashcow pile of shit with no direction or consistency. SoE knows they have a select group of people so addicted to their game, it wouldn't matter what they released and how often, their brainwashed customers would pay for it, which to this day, sadly enough, people still pay for.
Soooo, the brains behind Verant decided to go elsewhere and created Sigil, a company that is driven to make what they weren't able to on EQ with SoE around, but at the same time introduce new things we haven't seen in these games before. So yeah, Vanguard will basically be what EQ was originally intended but with next generation ideas mixed in or something like that.