I remember promises of DRM free builds for Reincarnation at least.

TDR 2000 will only appear here if enough people demand it. That's the only reason they released it on Steam, because Stainless themselves hate that game with a fiery passion and would like to forget it exists altogether.

What exactly is TDR as opposed to the other Carma games?

Reincarnation might get a DRM-free release. But they're actually still patching it pretty heavily right now and given that GOG doesn't yet have an adequate patch delivery platform, if they're going to release on GOG then they'd probably leave it until they've stopped tinkering.

They also mentioned car DLC too. While more cars have been added to the core game, they haven't had any DLC at all yet. Makes me wonder if they're building towards something here... TDR 2000 was the third game in the series. It wasn't developed by Stainless, but worse than that... far worse than that, it was developed by the devs behind Barbie Fashion Designer. It kinda showed.

I haven't played much of it, and it didn't seem that bad to me, but I think someone (it may have been Lazy Game Reviews) mentioned that there was more of a focus on the actual racing rather than carnage and destruction (although those were still very much there).
In general, people tend to consider it inferior to the first two games in terms of overall quality, partially attributed to the fact that it wasn't developed by Stainless. Thanks to that, the game's official site looks like this.

Wait, I thought that the 3rd game was just called Carmageddon 3, and yeah, I know that sucked. It sucked beyond suck. I didn't think that was related to TDR.

It was just poor. The bland level design. The bland opponents. The total lack of the atmosphere the first two had. Sound was barely there. But at least that did cut down on the constant screaming which admittedly was something of an improvement. Even the colour scheme seemed somewhat twee by comparison. Poor.

In the US, it was called Carmageddon 3: TDR 2000, apparently, but a lot of releases simply dropped the "3".

It might have been named differently in the states, as TDR 2000 is a reference to Death Race 2000, on which the original game is somewhat based.

Well now that I have been educated, why would we want it here? :P

To me it would be like getting Postal 3.

Ah, alright then. I barely remember anything about it. As a matter of fact, I'm not entirely sure if I ever got past the first race in that game.
Quoth the Steam page:

Stainless Games had no involvement in the development of Carmageddon: TDR 2000. So, you have been warned.

[...]

Yes, it's the game literally... SOME of you asked for! And so, in the spirit of "well, alright then, if you insist..." we present the third game in the Carmageddon series, in the knowledge that some of you Carma fans out there would like to have a complete Carmageddon collection in your Steam library. Nothing wrong with that.


Although I wonder if anyone will ever demand Carmageddon 64...

Would love to have Postal 3 on here.

Yeah, me too. After all, I also own Simon the Sorcerer 3D and Leisure Suit Larry: Magna Cum Laude here.

Magna Cum Laude isn't that bad, it just isn;t a LSL game. I recommend it to anyone who wants to play something but is too drunk to handle any kind of strategy or reflex.