Strengths: Climbs like a mountain goat. Rolls like I don't know what (maybe to be expected of a 29er). It is relatively agile.
Weaknesses: Seat and grips. Both are too hard for my liking. Also the seat seems to be too prone to being offset to easily. I.E. goes up or down if you bounce a little bit on the seat. The stock pedals were somehat bothersome as they do not provide sufficient grip in my opinion. Obviously all of those parts are easily replaceable so no major weaknesses. Other than that, there are no major issues.
I am coming from a TREK 4900 (2006) and have been comparing these bikes thoroughly. The brakes (Tektro Draco) on the Black forest are good and suffice for most cross country situations. I have not found the tires to be lacking at all, but I do mostly (only, maybe) ride in dry conditions. Shifters and derailleurs are decent although some might want to upgrade from just Deore on the rear derailleur. The bike actually seems to sit lower than my old 26" Trek 4900. I tend to hit the pedals more on the ground compared to the Trek. But I am still getting used to the 29er.
This bike seems light to me and rolls more easily. Climbs well and is agile. Would recommend it for beginners and semi-advanced.