The Good: Smooth ride, relatively light, pops off jumps nicely, GT brand components are surprisingly nice.
The Bad: At this price point, the fork is pretty decent, but on tall jumps that are short front-to-back, it could benefit from being a bit stiffer. Very nice for longer, flowy jumps though. The seat is horrible.
I ride at Ray's MTB Cleveland every week or so and have rented the Trek Ticket for the past 2 years. I loved the way the Ticket rode, but could not quite stomach the price of it so I compared its geometry to virtually every bike I could think of (crazy-looking spreadsheet)! I found that the GT Ruckus DJ Zero had as close of a geometry as I could get at a reasonable price and went for it, although I was a bit nervous about the potential weight. The bike turned out far better than I could have ever expected! It arrived weighing 28.9 lbs. I dropped a little weight by switching the seat/seatpost (fixed seat/seatpost was uncomfortable) and am in the process of upgrading the fork to a Manitou Circus Expert (.5 lb savings). The biggest thing I have been impressed with is how much less effort it is jump things. The chromoly frame (Ticket is aluminum) really springs off of the face of jumps and absorbs any rough landings. My knuckles are no longer sore after 5 hours at Ray's! The shorter chainstays and lower bottom bracket also helped with manualing and carving thru the S-turns.
Do not shy away from this bike thinking it will be heavy or because it has GT-brand components. I've worked at a bike shop in the past and owned a lot of various kinds of bikes and feel qualified to say the parts on this are really nice. Add your own seat, grips, and pedals and you will LOVE this bike.