Was there an edition of the core rulebook printed that included the errata?

Doubt it. That's too expensive on the production end with no guarantee of returns on the sales end.

Foreign Rulebooks contain it to some degree... e.g. the german rulebook contains part of the errataed rules, but weapon stats are still the old.

I thought the errata'd weapon stats were presented as an optional rule, instead of actual error correction? If so, I would not expect them to be altered.

There were, however, a lot of other corrections.

FYI, the books following the release of the optional weapon stat changes all use weapons whose stats reflect the changes.

They're not going to release a new corebook with post-release errata incorporated because such a re-release would never make enough money to offset the cost.

Well, they would not reprint the book JUST to add the errata, but they could certainly include the errata in future printings. They did so with Edge of the Empire.

So for Deathwatch, was there only the one printing, then?

In Edge I believe you are referring to the paid Beta vs the actual release edition. Those were technically 2 separate products. FFG budgeted for the full release when they created the Beta (and saved money on the Beta in a number of ways that they could recoup with the full edition).

Putting out an "updated core" is more than just copy-pasting in errata rules. You have to change and update page layouts and tables, increased word count affects printing costs, and the likelihood of an updated pdf making the sales in numbers compared to the original release run is unlikely. These aren't factors present with the non-free Edge/AoR Beta, because the Beta was never intended to be the final release and FFG was prepared to make the changes in advance, versus having to retroactively apply changes in the case of errata. It's not really a comparable analogy.

I don't know if there was one print run, I do believe they won't incur the cost of everything I mentioned on top of a new printing when they can just keep the original layout and refer people to the errata online.

I'm actually referring to the second printing of the Edge of the Empire Core Rulebook. I asked via official channels and received this reply from the game's Lead Developer, Sam Stewart:

"We endeavor to include the most up to date errata in all subsequent printings of books, although obviously there is some lag time between beginning the publishing process and release. As long as the errata was released before we began reprinting, it should be included."

Judging by that, I'd say it's FFG policy to include errata in subsequent printings. If that has not happened with Deathwatch, then I would assume it's because there have not been any subsequent printings. The fact that the book was on sale for half-price this holiday season would seem to lend support to the idea that it did not do quite well enough for additional printings, but that's just an educated guess.

Different game lines, different development teams. At this point DW isn't new enough to be worth putting out a corrected book. We'll see if DH2 takes the same approach.

It's a stretch to say it's FFG policy just because the Star Wars devs do it. Good for them for being able to afford it. Personally I think it's kind of wasteful in a business sense, but whatever.

That may be the case, though I would find it strange that their design teams operated differently with regard to reprints.

As for it being a waste, I assume the second printing of EotE was made in response to supply not meeting demand. Probably they sold out the first print run and had more orders to fill. It was likely a simple matter to add the errata to the book, because there is so little of it for that particular game.

Deathwatch, on the other hand, has a ton of errata, so I think your point about the scope of the changes needed to incorporate it is likely the primary reason it would not be done in a future printing.

I'm sort of disappointed that we likely won't get a second edition of Deathwatch someday. I've come across a lot of typos during my reading, and it feels like a bit of a rushed job. It could certainly use another pass either in a reprint or second edition, but I agree with you it's not likely to happen, especially since the post announcing Dark heresy Second Edition explicitly state that there is no intention to do second editions of the other 40KRP books.

Ah well. The game is perfectly viable as it now stands. Just wish it were a bit more polished

That may be the case, though I would find it strange that their design teams operated differently with regard to reprints.

I wouldn't be surprised if it's because Star Wars is a much bigger, more lucrative and valuable IP.

Very true.