Oh wow. They sure have. They have those orange and white barricades up around the site. I still haven't seen the building elevations for it, though. At 17 floors it'll probably be the same height as Hyatt Place.
Look just above the roofline of Whitley.
http://oxblue.com/open/tournee/jwmarriottaustin
That's 7 construction sites that have been visible in that view.
Hampton Inn University Area
JW Marriott
Hyatt Place
Whitley
Callaway House
3rd & Colorado
Westin Hotel
It would have been 9 if the 416 Congress Hotel and Austin Hotel hotels had happened.