Yep, I got that stylus pictured above. $23 gets you the best DSi stylus available for your system. However, I must say, it's not as impressive as the stylus upgrade between DS and DS Lite. The metallic finish isn't as clean as the chrome finish on the DS Lite stylus, and the spring-loaded tip is a mixed blessing; it's nice to take the 'force' away from the screen when you push the stylus a bit too hard, but you can feel the tip going into the stylus and it feels a bit scratchy; makes me feel like I'm scratching the screen!
I would say, if you have the DS Lite Pro stylus, keep it and use it on your DSi; it fits perfectly and works just as well. If you don't have a Pro stylus from PDA Panache, get the DS Lite one, even if you have a DSi. The only reason to own this specific stylus is if you like the gold highlights on it; everything else is the same, or even worse, than the DS Lite model. I'm disappointed, but as the #1 DS Fan I had to have this :)
UPDATE: This might not be too bad, actually. I've spent more time with this stylus, and I'm really liking the excellent grip it has; it just stays in your fingers really nicely. I'm also really enjoying the extra length, but that's probably because this is the first DSi-specific stylus I've used.