Very, very little is known at this time. The NHL has yet to respond to the report, and was not even aware of the arrest as of 7:00 PM PST.
About all we know at this point is that he was arrested at a Vegas day club.
We will keep this post updated with more information as it becomes available. In the mean-time, I would like to encourage our commenters to be sensitive to the subject at hand. Please avoid crass jokes and, at least temporarily, avoid discussing how this affects his impending UFA status. We don't know much about Jarret Stoll and his situation just yet, but we know that drugs and addiction are serious problems that affect pretty much all of us in one way or another.
9:10 PM: Rich Hammond of the Orange County Register reports that Stoll is out of police custody; he also mentioned that a court hearing was set for tomorrow (April 17th), though it now appears that hearing will likely take place further in the future.
10:05 PM: The club has released a statement:
We are aware of police reports out of Clark County, Nevada regarding Jarret Stoll. Our organization is concerned and has begun conducting a thorough internal investigation. While we continue to actively gather facts, we are withholding further comment at this time.