Stats? Here's my attempt at some stats (somewhat in line with Mearls' makeover articles and what we know of 4E):
Vampire Lord (Template)
This template can be applied to any living humanoid creature.
Type: The type changes to Elite Undead
Level: Increase level by 2
Speed: Gains climb speed equal to land speed
Defenses: Increase all defenses by +2
Attacks: Gains bite attack (1d6 base damage for medium vampire lords, modified by size; heals 5 hp per successful bite attack); increase base attack by +2
Skills: Gains Focus in the following skills: Deception, Initiative, Insight, Perception, Persuasion, and Stealth
Blood pool: Vampire lord can expend his blood pool as an immediate action for one of the following benefits:
(1) Gain another use of one of his per encounter abilities
(2) Resist Frenzy
(3) Heal 5 HP/level
(4) Ignore one vulnerability for one round
Vampire lord can refresh his blood pool by performing a coup de grace with his bite attack.
Frenzy: At half hp, vampire lord descends into a bloodlust-induced frenzy; he can only attack with his bite and cannot use any special abilities until the end of the encounter. Vampire lord may expend his blood pool to prevent frenzy. While in frenzy, vampire lord gains a bonus equal to 1/2 his level to attack and damage rolls, and his speed increases by 4 squares.
Gaseous form: Immediate action; per encounter; vampire lord also reverts to gaseous form automatically if reduced to 0 hp.
Special Abilities:
Charming gaze: Immediate action; target: living humanoid; unlimited uses; Level + Cha modifier vs. target Will defense; target attitude towards vampire becomes friendly
Dominating gaze: Standard action; target: living humanoid; per encounter; Level + Cha modifier vs. target Will defense; vampire controls target's actions
Alternate form, lesser: Swift action; bat or wolf; unlimited uses
Alternate form, greate: Standard action; dire bat or dire wolf; per encounter
Vulnerabilities:
(1) Garlic causes the vampire lord to become nauseated
(2) Any believer with a holy symbol of his faith can try to turn the vampire as a cleric of his level
(3) Direct exposure to sunlight causes the vampire lord to lose 5 hp/level per round of exposure.
EDIT: And yes, if it's not immediately obvious, I ripped some of those things from WoD - particularly the frenzy and blood pool (which is, I think, similar to how Action Points are going to work in 4E).