Bloodlines do not in most ways affect the ECL of a character, so they do not provide HD/HP/SP. They do give bonus feats, abilities, skills. For a major Bloodline, they must take a level by ECL 3, another one by ECL 6 and the final one by ECL 12.
This being said, they do gain bloodline traits at varying Character Levels, not just when they 'take' the bloodline.
Here is the full list for Major Vampire Bloodline:
Character Level/Trait
1st/+2 on Climb checks
2nd/Stealthy (Feat)
3rd/Strength +1
4th/Resistance to cold 5 (Ex)
5th/Vampire affinity +2
6th/+1 to natural armor
7th/+2 on Search checks
8th/Resistance to electricity 5 (Ex)
9th/Charisma +1
10th/Lightning Reflexes (Feat)
11th/Vampire affinity +4
12th/Alertness (Feat)
13th/+2 on Sense Motive checks
14th/Improved Initiative (Feat)
15th/Dexterity +1
16th/Suggestion 1/day (Spell)
17th/Vampire Affinity +6
18th/+1 to natural armor
19th/+2 on Bluff checks
20th/Damage Reduction 5/silver
On the vampire affinity, you gain the specified bonus on all Bluff, Diplomacy, Gather Info, Intimidate, and Perform checks made to interact with vampires. On the Feats, if you already have the specified Feat then you can choose another.
So the boots are nice. the drawback is that you have to take the bloodline at the specified levels, or you cannot continue to gain the abilities at the specified Character Level.
The other wrinkle in the mechanics is as follows:
"A bloodline level grant no increase in base attack bonus or base save bonuses, no hit points or skill points, and no class features. It counts as a normal class level (with no class skills) for the purpose of determining maximum skill ranks. Character's bloodline level should be included when calculating an character ability based on his class levels (such as caster level for spell-casting characters, or save DCs for characters with special abilities whose DCs are based on class level). The character doesn't gain any abilities, spells known or spells per day from the addition of the bloodline levels, though - only the calculation so their level-based abilities are affected.
So to clarify a bit more, this is from the FAQ in UA:
..Your bloodline levels stack with your normal class levels "when calculating any character ability based on ...class levels". The key work here is calculate..it means when you use the level as part of some mathematical determination of the class feature's power or uses. Abilities that say 'add your class level' count, but abilities that say 'a character of level x gains this effect' don't.
So from an experience table standpoint, when the character has achieved the XP to move to Character level 3 they will take the bloodline 'rank' instead. then they would need to achieve sufficient additional XP to qualify for the Class rank of 3 before gaining that ECL.
Hopefully this is not too much errata. Where and how does the template come into play?
thanks!
sean