XpUser,
I got to be straight with you on this FUD bulletin. A substantial part of the OEM tattoo allegations (over the years) are not resoundingly supported by the evidence out there & on a public forum such as this, utmost effort should be made to corroborate the validity of our assertions.
I don't quite recall whom it was few years back on this forum that categorically made the same statement about Gateway's OEM supplied OS (XP) disc not working on non-propietary machines. As it turns out - that was largely false in cases where the OEM has been generous enough to include a "system disc" with the machine.
Furthermore, more than a few folks (myself included) had installed XP on a custom built system using an OEM supplied XP disc - which was in fact identical (content but not cosmetic wise) to what you'd have gotten if you had purchased a retail XP disc.
However, these type of discs should not be confused with those "image" discs many OEMs sometimes supply with their systems popularly referred to as recovery discs. Those are the ones that are notorious for not working with DIY systems.
While I really don't have statistics on the proliferation of alleged system "tattooing" among OEMs, incident rates suggest HP's notoriety with the mechanism. But what I do know is that there isn't anything implemented within a Dell supplied Vista Ultimate DVD that will make it act differently from what you pick up from retail outlet. How do I know?
Well - I happened to have experimented with both. I am not sure if the same can be said with other OEMs (especially with HP) but I would assume the same can be found with a Gateway supplied Vista DVD.
BTW, when I go to a store like BestBuy or Circuit City, I don't even bother discussing technical details with the floor staff, a lot of times the information you get from them is a good as being fabricated on a smoke break.
Lastly, I'd be interested in someone sharing experiments related to this OEM/tattooed Vista disc subject so we can really come up with a pattern if any on this IMO widely distorted perception about the OEM media DVD.