Synopsis: 2 thumbs up!
I admit I'm a sucker for the gorgeous Vaja leather cases since I got one for my old Sony NW-HD5 music player a few years back. My gf is still using her Vaja Pearl case after 2+ years. The Vaja leather cases have a Borg-like integration with the electronic devices they cover, and my new 8900 case is no exception.
I purchased the Vaja Balance case (with no clip option) from the Vaja website (vajacases.com). These are custom-made cases and mine arrived (from Argentina) 2.5 weeks after placing my order. I got the green gables color, which is a bit darker/greyish and a more subtle green than their website pic. I love the color. (You can also get the case with a removable clip or a small chain with a clasp; both attach to a small stud on back of the case. I just slip my BB in my pocket, case and all.)
The Balance case is a play-through case with a front cutout for the screen and keyboard. The case fits like a snug glove, and becomes one with the 8900. (I have a full-body BSE skin on my 8900, and it fits in the case perfectly.) Some comments on the case itself, before I get to the fit and functionality:
Vaja uses high-quality, thin leather with a fine, subtle grain. There are cutouts for the side volume rocker, micro-usb charging port, and both function keys. There's a thin screened cutout for the front speaker, and a small cutout on the top right with a cloudy plastic insert for the LED indicator. There's also a tiny screened cutout on the bottom edge, left side, and I don't even know what the hole under there is for. (Is that the mic?) The camera lens/flash on back are enclosed by an elongated oval cutout as well. None of these cutouts have exposed stitching--just smooth, turned-in leather edges. Very clean and neat.
The back of the case is a stiff flat surface that matches the outside silhouette of the 8900. The sides and bottom of the case are stitched to this back along the edges with tight, neat stitches that are dyed to match the leather. Very subtle and neat. The bottom corners of the case are open, and the top of the sides end symmetrically where the right-side headphone jack is. (This is so you can grasp the upper corners of the 8900 and pull it out of the case.)
The inside of the case front and sides is covered with a thin fabric, and the inside of the stiff back is covered with leather embossed with "Vaja" in a repeating diagonal pattern. Even the edges and finish on the inside of the case are neat and flawless, with no exposed rough edges. Oh yeah--and the leather smells great!
Now for how it works. The 8900 slides in smoothly and snugly. Right away, the distinction between case and blackberry becomes blurred, as they form a symbiotic whole. The front is really nice--the cutout around the screen widens slightly around the keyboard area. Again, the edges are all thin and smooth, allowing full screen visibility and access to the endmost keys with no problem. This clean edge finish of the Vaja cases is one of my favorite aspects--it really is beautiful. There is also a uniform sliver of chrome visible around the edges of the keyboard.
The cutouts on the side buttons are perfectly placed. You may need to use the tip or edge of your finger to press them through the cutouts, but the buttons don't feel obstructed. The top front of the case follows the contour of the 8900, so it's a bit lower than the downward sloping top of the 8900.
The interesting part of this case is the stiff back panel. The edges are smooth and hard, with stitching along the upper/lower surfaces but not the edge itself. The edges of the back actually stick out a tiny bit because the sides of the case slope inward a bit (following the side contour of the 8900). But the back panel has the same outline as the overall 8900 perimeter, so it doesn't extend beyond the phone itself. What I found is that this makes the 8900 much easier to grip no matter how you hold it, with this smooth edge of the back panel providing a little ledge that is comfortable to hold. (Even when I occasionally do a bit of one-handed typing with a bit of a thumb stretch!)
Overall, the Vaja case feels like a part of the 8900. It is very comfortable and doesn't make the 8900 feel bulky at all, and is the most elegant case I've seen. Check out the pics on their website to see the details.