Since vampires (and some other character options) start with 2 IP, I want to just make sure that it means that if, say, a vampire adept takes 1 level of Improved Reflexes, it won't do anything for him besides increase Reaction by 1. Am I correct in thinking that they wouldn't get a 3rd IP unless they have 2 levels of Improved Reflexes, or a mage casts Increase Reflexes on them with at least 3 hits?

Emphasis mine. Considering all of those rules, I'd say that the only ways to get a vampire (or similar) above 2 IP would, as you thought, be to take Improved Reflexes 2 or to have a mage hit them with Increase Reflexes with 3+ hits. At that point, you're not really stacking initiative bonuses, but overriding the character's innate initiative bonus. In addition, you could reasonably extrapolate that you could override it with bioware or cyberware of sufficient rating, but that's likely a game-by-game call.

And whay would you think that? Your quotes say otherwise...

Nope. The quotes say that the bonuses can't be combined. Thus, you can't be a vampire (getting +1 IP), and then get, say, Improved Reflexes 1 to wind up with 3 IP. I'm just assuming that it's like most other things in SR in regard to stacking (sans a few explicit exceptions like armor) and the highest bonus that you have available is the one that applies. This has limited usefulness, but if a vampire picked up Wired Reflexes 2, he'd have his 3 IP. Now let's say that the vampire is placed in some situation where his Wired Reflexes are inoperable - at that point, he'd revert to his natural IP bonus and still have 2 IP, where a lot of other metahumans would be out of luck (and I'm basing this on it not saying anywhere that the vampire loses his natural IP bonus if he enhances it some other way - I haven't read the vampire section today =P).

That, they don't say:

"cannot be combined with technological or other magical increases to Initiative"

And the passes of a vampire are neither - they don't disappear in voids and they certainly aren't based technology, either. It's not even certain that having more than one pass is an initative enhancement, at all...
Just the 4 passes limit remains.

This shouldn't even be asked. It doesn't even matter what the description on reflexbooster/synaptic accelerater etc. says. The list of infected attribute modifiers (Companion, page 79) state clearly that they have 2 IP's natural which won't stack with anything.

There is a * after initative and the * is explained just two centimeters down.

Which, in turn, leads back to my thought that a higher IP bonus would override an infected's innate bonus. I really think that that's the way that the rules are intended to work here.

yeas thats exactly how it works, it's all explaint in RC page 79.

So my original assertion is correct. Please disregard the rest of the thread =P

Well, with the one addition that this is pretty clear - any Cyber- or Bioware would override the innate bonus and provide its own instead, as well. So, 2 IP until you get something that gives you more.

HMHVV is an Awakaned Disease. Thus, the effects it has on a character are magical in nature.

Haven't all the possible viewpoints been covered yet?
1. The OP was right, you need something that gives a total over MORE than the vampire's base 2 IP's. Thus, you need Improved Reflexes with 3 hits or similar.
2. Nothing.

Those seem to ba all the viewpoints expressed. Everyone seems to agree, so why is there argument?

You're wrong. This is Dumpshock. We don't have arguments here.

There is only the unity.

Does said effect fade in a Mana Void? If not, it's not magical.

And of course, that cop-out doesn't even work for normal critters with more than one IP, benefiting from a transfered adept power.

Correction:

There is only unity in the case of disunity. All other cases result in disunity.

Whether or not it's a Magic effect, the question has been answered to a reasonable degree of certainty - the highest IP bonus applies, and if it's higher than the Vampire's natural IP bonus, the natural bonus gets overridden. So it is writ, so shall it be. RAW, end of story.

Objection:

If cases of disunity cause unity to exist, and all other cases cause disunity, would this not lead to disunity solely existing where disunity did not exist (cases of unity, or perhaps partial unity, which further would be disunity due to factionalism), and unity solely existing where disunity exists, thus leading to disunity and unity both existing where disunity does AND does not exist?
Besides the semantic failure of my above sentence, doesn't this create a logical black hole?

As for Dumpshock, I should haved remembered the cardinal rule.