They basically released one title with minimal DRM (I think it still had a disc-check). And clearly that didn't end well.

About the cracks - actually Ubi may be right about the games not being cracked yet (we all know it's a matter of time). There are conflicting reports on whether it works or not (no, I am not talking about Ubi's reports :P), and that usually means that things don't work as they should. But it doesn't matter anyway - it will most likely be solved by the end of the week.
All this would be pretty funny if it wasn't for the people who actually bought the game (you can say it's their own fault for accepting this DRM, but still...).

If it is true or not is irrelevant. The fact is their servers should have been capable of dealing with such an attack as they would have been muppets not to expect one. Even if Ubisoft are telling the truth it still means that you now cannot play that game if some hackers decide to take out their jollies on Ubisoft.

You also can't play your Steam games if some hackers "decide to take out their jollies on" Valve.
You also can't activate your Securom or Impulse games if the same happens to Securom and Stardock (respectively).
You can't download your GoG games if CD Projekt gets hit.
Seriously, if this really WAS "hackers" and the like, Ubi can't really do anything. A dedicated group of idiots will always succeed (especially if they are just doing a DDoS attack). It just so happens that Ubi was a decent target because everyone has their panties in a twist right now. There are precautions and preventative measures (if Ubi did those, we don't know), but this happens.
You might as well hate the internet because you can't get updates from your favorite news site if they get hit.

I have no illusions that my choice to not buy from them will make a bit of difference, but at least my conscience will be clear when it comes to throwing blame around for future occurrences of Ubi's bullshit. I can say with confidence, "hey, you have no one to blame but yourself, you kept buying stuff from them, I didn't" (I mean "you" in general, not you in particular... love the English language). I would love to reward good behavior in a company like Ubi, provided there is any good behavior to reward. Even before the announcement of their new "DRM that is not DRM", they were acting like a company run by a Dark Lord of the Sith... either that or Dick Cheney... but the point is, they have been doing nothing worth rewarding and it doesn't look like they intend to in the future.
On top of that, you have the bald-faced, blatant and instantly provable lies and I can no longer trust anything they say. At least when one of the other "bigs" like Activision or EA lies to us, it is usually a lie of omission or nothing more than a "little white lie", not something that could be easily proven wrong with a half-hearted Google search. It just goes to show what a low opinion Ubi has of the intelligence of their customers; first that they tried to convince us that this "service" was a good feature of the games, second that they lied about the existence of cracked versions. If it isn't a case of a low opinion of our intelligence, then it is simply incompetence, which while not as insulting, is still a reason to not have any kind of dealings with them.
Uh, no. This was flat-out proven wrong a few days ago when the Steam servers went down. All games, except those that are multiplayer only, functioned normally despite the lack of a server connection. This was without using "offline mode" prior to the outage.

You have missed the point. AC2 and Silent Hunter 5 not to mention Settlers VII require a CONSTANT internet connection to play. None of your examples do. Basically Ubisoft's system has more in common with an MMO like WoW and when WoW servers go down, Blizzard actually credit you with time to your account. Ubisoft cannot.

Ubisofts response to servers going down....

I've yet to run into any problems with AC2... well the only issue I had was installing, ended up using a portable DVD reader but that is more of an issue of my laptop getting old then a bad crack.....
(Yet another game they would not ship to Iraq, yet the ps3 version was able to be shipped so meh....whatever)

Since we're talking about singleplayer games, i think this UBI system is very close to what goes on with download to play services like GameTap or Metaboli, where a constant and uninterrupted connection is required.

Prince of Persia and Endwar both had no DRM at all. At around the same time they killed off the Far Cry 2 DRM. I think that Hawx was DRM-free too, but don't quote me on that. Regardless, there was a definite period (albeit brief) in which they had a completely DRM free policy.

I'd love to see sales figures on those drm free games against this new method and their old 3 install limit securom method. They obviously didn't sell as well as they liked drm free but is that because these are games less people are intrested in? It would be nice to also see a game of Assassin creeds 2 level go drm free and see how the sales hold up with that as well.

Ubisoft are, right now, probably the absolute worst company to support. Activision are extremely damaging to the industry as Kotick treats gamers like idiots and is proven right time and time again. But at least their games are playable. For those who'd want to play them.
I'm definitely not suggesting you support Ubisoft as there's nothing commendable about them at the moment. Their developers paid heed to criticisms of Assassin's Creed, then Ubisoft blew that to hell with the most ridiculous DRM scheme in history.
But all publishers are like this. They've all got skeletons in their closets. You can't realistically boycott them all without giving up gaming. So until Ubisoft have some sense beaten into them they should effectively remain boycotted. But not because they're Ubisoft. But because of their current shitty practices.

Ouch, they do that now ? I thought they were only delaying activation in certain region, I didn't knew they were going as far as preventing games from being activated at all...

I don't think they actually have done it yet, but they do have the ability to do it now. AFAIK, they've only done the regional blocking as you describe, which is bad enough in itself.