I portuguese!! I'm not worried at all, here at my school no teacher knows how to work with a Nspire, silly i know but whenever a teacher of mine asks me for a calculator, i bring mine already in a calculate sheet and he just looks at the calculator and says "I don't get any of this, someone bring a normal calculator!", its just like Ti Nspire doesn't have big black number on the center witha white background, it really must be a hard job to find such keys!
So i'm fine though i wont bring the CAS to the exam.

It is, indeed, flat out irresponsible.

Excatly. This attempt to prevent the usage of Linux on a platform which can run it (and whose Linux support is in the process of mainlining) will almost certainly attract a new class of attackers on the platform at some point: skilled people, who have no special interest in the expensive, underpowered platform in itself, but are infuriated any kind of blatant disrespect for users' basic rights, which makes them willing to spend free time and money on punishing the manufacturer. That's exactly the type of persons who blew the PS3 castle to smithereens. Perhaps the "nLaunch team" / "nLaunch CX guy" already belong to that group, we don't know...
If TI EdTech reacts inappropriately to the inevitable future attacks, like Sony did, then they take the chance of infuriating yet another class of attackers, even more harmful to the interests they're so hell-bent on trying to safeguard. The kind of attackers who can deeply penetrate network infrastructure and computer systems. In such an event, I think that the top-level managers to whom I patiently explained all of the above and more (and their successors, since high-level management people at TI often swap jobs) will be fired for incompetence.

but what is good for the community as a whole.

Oh, god... what kind of heinous crime does TI have to do for everybody to really wake up and start facing the truth, if even the current episode still isn't enough ?
TI is milking customers with underpowered products sold at very high price tags for such limited power and storage space; they're treating customers as foes; they're pissing on their basic rights.

Second: TI needs to be on tests.

TI is on tests even with open calculators, witness the whole TI-Z80 series or the Prizm. Lockdown is in no way a requirement. Their trouble with the Nspire line is because it is not open. The solution is openness.

Third: We could just crack the signing keys on the boot1 and/or boot2 and/or OS itself. TI might not even come after the community this time!

No, we could not. The topic has already been discussed (too) many times on the forum, look out for the topics... We cannot just do what we did with the TI-Z80 and TI-68k series.

(This is the optimist in me talking)

The completely unrealistic optimist who doesn't know what he's talking about, yeah. Sorry.

I don't think raging at TI is the right thing to do right now.

Raging creates resent. Resent is one of the three most powerful human feelings, one of those who get people out of their way. Another feeling of the triplet can help further: pride, for those who will make it, of slapping the silly manufacturer in the face, another time.
Getting people (and a larger number of people) out of their way, to fight back, is exactly what we need.

You don't want them hating us any more.

They do want people to hate them even more.

I'm well aware of their priorities, but they're no valid excuse for blatant disrespect towards users
As a result of their actions against users, and the predictable retaliations (which, for maximum impact, should occur around the best time of the year for inconveniencing TI EdTech and exam testing), even their target audience is likely to hate them.

So far my concern of the TI policy to lock down the NSpire for third-party applications is only to try make alive the need of a expensive calculator in university.
However in my University (IST), the use of a CAS calculator is pointless 
Even recentelly if exams that requires numerical calcultations, you can bring a smartphone to load a calculator application and use it. 
It's because the professors that teaches the course can check and make caution to avoid cheating between the students, and they think now the calculators of any kind, due to cheap Android phones, are becoming an obsolete technology.
When I make the last exam of introductory Nuclear Physics for my Ph.D. graduate, I use Maxima on Android to solve the calculations with my Samsung Galaxy Mini without problems. The only restrition is to use when is only needed, and then return to the desk openly to professor line-of-view to avoid cheating. (Even in convential calculators you can cheat  )

This means one big thing: why wasting almost €200 for a NSpire CX with a poor CAS, since you can use a smartphone that cost less than €100 which you can install a much better CAS (Maxima), and you can use during classes other powerfull applications ?! 

Well, in France you can't use a phone in high school, so you're forced to buy a crappy TI-82 Stats for €50 (at least).