Yes, he for all intents and purposes died, due to the Time Limit Virus Restrictor unleashed within him. The whole reason Nero cooperated with Hojo in the first place, was so that Omega would be used to revive Weiss again.
Thanks, always good to learn more things about the plot in ff7 that would confuse the hell out of the average person. But if Weiss was revived by Hojo, and then Hojo was removed, why did he still become Omega? Or was he too injured to live and had to become Omega?
That's the questionable part, Hojo is like "nooooo, with Nero entering this body were to impure for Omega" then Weiss walks into Omega anyway and we need to fight him as Chaos to resolve the situation. Though yeah, he could just become a puppet due to losing his purity.
Sounds like Weiss has some pretty shitty luck. I guess I'd give that plot a decent score and another good thing the compilation contributed, although the manner in which the plot was told was confusing to the point of frustration.
On a different note: The part in DoC where Vincent goes into the sewers and you have to battle the teenage mutant ninja turtles from Cosmo Canyon was pretty sweet.