Ok, I rarely post here, mostly just read. I've followed the story since it broke. I watched the press conference on CNN. Maybe they picked the worst possible guy from the sheriff's office to speak to the media, but if he is indicative of the competency level of the people investigating this, I'll wait until all the forensic evidence comes back from the crime lab before saying with 100% certainty that Benoit did this. We don't have a full veiw of the timeline here, first it was Saturday for Nancy, Sunday for Daniel, and Monday for Chris. Now it's Friday for Nancy, Saturday morning for Daniel, and either late Saturday or early Sunday for Chris. If Chris wasn't home on Friday(and I'm not saying one way or the other), that leaves some room for doubt. Until we actually know the timeline for the deaths, Chris's whereabouts in relation to the timeline, and when the text messages were sent in relation to the time of death, there isn't any way to know for sure what happened.
On the subject of the text messages, someone mentioned earlier that sometimes text messages show up quickly or many hours later. That's true, but unless the "sent" folder on Benoit's phone was erased, it should exactly when the messages were sent(at least that's how my phone works).
The most likely scenario is Chris snapped for some reason and killed his family then himself. It is however entirely plausible(while not necessarily likely) that someone was holding Nancy hostage, forced the call to Chris then killed her, then Daniel was killed before Chris came home. Chris comes home, his family is dead, and then he kills himself. I'm not saying that's how it went down, or even that it's likely that it happened that way. It is however one possible scenario that could have unfolded, and until we know a more exact timeline as well as other facts it's impossible to say with absolute certainty what happened.