Well, here is what we do know:
We know based on interview comments from James Labrie auditions were held approximately around the 2nd and 3rd weeks of November
Jan 4th, John Petrucci posted that was the 1st day in the recording studio with the new drummer.
Aquiles Priester: had a gig with his band on Nov 27th, was at NAMM, and then went out on a clinic tour, and has dates with Hagar over the next several months.
http://www.hangar.mus.br/ing/agenda.htm
If he is the guy, it makes sense why they're not announcing it, so he can finish out his obligations. But at the same time, if he's the guy, there isn't really a window he could be working on the album with DT. So I have my doubts.
Bobby Jarzombek was out with Sebastion Bach for most of October, and was touring with Halford for November, and he recently posted he spent his early January recording with a Fates Warning side project, and it currently doing a small European tour with Fates Warning. No window to do it in, he's out.
Mark Zonder posted on his Facebook a while back that he was never even asked to audition.
It has been reported that Marco Minnemann
has denied being the guy.
Mike Mangini is a name often rumored.
His facebook is rarely updated, so it's of no help.
There is this tid bit of evidence:
http://www.roadrunnerrecords.com/blabbermouth.net/news.aspx?mode=Article&newsitemID=154009
"Mike Mangini left [Berklee] at the end of last semester, so although those are some extremely huge shoes to fill, things are going really well. Mike always helps me out, to make sure I know what's going on before I start. So I'm really excited for the semester.
Although Mike is still listed on the Berklee website. But Mangini leaves Berklee right around the time of the auditions? Coincidence?
But if he was the man, there appears be to no reason to not announce it.
And in other news, Mike Portnoy has posted on his FB/twitter he is in the studio doing a side project with the singer from Symphony X, which means Jason Rullo isn't doing anything right now. Humm.....