On a separate note, let me just say the Acekard 2 with its AKAIO firmware is probably the best flash cart on the market. It's considerably cheaper than some equally impressive alternatives, and the AKAIO firmware has the best compatibility out of anything so far. It's also incredibly easy to use (just drag onto your microSD and you're set), and the interface can be customized with downloadable skins. It made my experience so much more clean-cut.
The touch controls are brilliant and the games are great, but I obviously have some complaints. The D-pad on the DS Lite is awful; it feels very loose and the diagonals are incredibly weak. It's very hard to move freely with the D-pad, and really holds back your ability to move during gameplay. Also, being a Sony guy and an owner of a PSP, I couldn't help but compare its hardware specs to the PSP. I love the style of graphics in games like Final Fantasy IV and Phantom Hourglass, but I just felt like something was missing. I'm used to the powerful visuals on the PSP, and the higher quality audio. The DS makes up for it with its own ingenuity (which is why its sold so much better), but the PSP still holds a place in my heart and will probably remain the better system in my book.
Here's Final Fantasy IV for the DS
And here's Crisis Core: Final Fantasy VII for the PSP. I love the cute graphical direction of Final Fantasy IV, so I'm not complaining about its graphics in the least. Crisis Core has some very impressive visuals for a handheld game, and clearly demonstrates the PSP's graphical superiority. It's unfair to compare the two, but you can see why it might be a weird transition.