Some TU7 Survival worlds did generate netherwart even before the bug fix update. For some reason, the bug did not affect those worlds in the first place. So, if you have a TU7 survival world and have not already looked thoroughly for netherwart in it, it might have netherwart... but that netherwart was probably already there before the bug fix anyway. If you have a TU7 world that you have already searched thoroughly for netherwart and you didn't find it, the bug fix update would NOT have put netherwart into that world.
If you start a new world using that same seed, you will probably find that the fortress has moved to a different location (that is, IF it generated at all in the same seed created in TU7). The netherwart, however, is apparently still not generating on a small percentage of the newly created seeds (although there is always some chance (a small chance) that the people reporting this just haven't located the netherwart yet and may still find it if they keep searching). Only time will tell. What is known is that the bug fix has caused netherwart to generate in a higher percentage of seeds than prior to the bug fix. Fortresses, which were not generating at all in some worlds prior to the bug fix, now appear to be generating (at least in part) in all worlds created after the bug fix.
I'm not 100% on this so if anyone else wants to back this up...
Man, i am a nether noob so could you explain to me that?
If you start a new world using that same seed, you will probably find that the fortress has moved to a different location (that is, IF it generated at all in the same seed created in TU7). The netherwart, however, is apparently still not generating on a small percentage of the newly created seeds (although there is always some chance (a small chance) that the people reporting this just haven't located the netherwart yet and may still find it if they keep searching). Only time will tell. What is known is that the bug fix has caused netherwart to generate in a higher percentage of seeds than prior to the bug fix. Fortresses, which were not generating at all in some worlds prior to the bug fix, now appear to be generating (at least in part) in all worlds created after the bug fix.