Alright, I've been testing the monitor for some hours now, and here are my thoughts on this upgrade.
Included: Monitor Stand, Instruction Leaflets, Driver CD, VGA Cable, DVI-D Cable, PC USB Connector Cable, Power Cable. Note that this monitor doesn't have an HDMI port.
Exterior: U2412M has a very nice black matte finish (you can also get it in silver), and the included monitor stand is really easy to attach or remove, it's basically a push-click system. The stand is also very sturdy for a plastic piece - it doesn't wobble, and the monitor hardly ever shakes if you don't bump into your table. The monitor tilting (sideways, up & down) works smoothly, and isn't too loose if you accidentally bump it with your hand while plugging USB devices. The height adjustment is the icing on the cake - it just seems so effortless, yet you can be sure that it doesn't move on its own. Bonus points for the internal power supply!
Defect Status: I couldn't believe my luck when I confirmed that there weren't any(!) dead or stuck pixels on this 24" monitor. I guess Dell puts more emphasis on quality control than LG. Or maybe I just got lucky here. There's very little backlight bleeding in my unit, so little in fact that I can only spot it with a full black screen, which is a rare occurrence.
Panel Quality: The panel quality is pretty obvious in use after switching from my old TN panel to this low-end IPS one. The color accuracy is pretty good out of the box as well, but a calibrated .icc profile will provide even better results. The Standard mode is the most accurate mode out of the box. U2412M is everything you'd expect from an (e-)IPS panel in this price range according to my research. However, if you're coming off a glossy monitor, this Dell UltraSharp may not appeal to you, as the anti-glare coating is present. My old monitor's panel also has a matte finish, so personally I don't really notice it unless I look for it.
Menu Design: The menu system for making hardware side tweaks and calibrations is pretty clear in my opinion, and you can also change the default functions for the quick keys. It has automatic input source detection on by default (VGA, DVI-D, DisplayPort).
Windows Environment: I haven't encountered any issues in standard use, although you may want to tweak your system font size / style depending on how small text you're comfortable reading with each font style. Text sharpness and readability are above average even on default Windows font settings, and this is at only 50% monitor sharpness (default). If you're looking for a monitor for text editing purposes, I'd still shop around, although I've heard several coders mention their like for this monitor. It's definitely too bright on its default setting, so I dropped the Brightness level to 35%. Note that I don't have to deal with anything but artificial lighting.
Gaming: I haven't noticed any ghosting while playing games, even though this monitor does have a higher latency value than most TN panels. And there's basically no input lag. The color reproduction is excellent at this price. Altogether I've been pleased with U2412M's gaming performance, and my conclusion is that it's unlikely that you'll notice any major ghosting even in fast paced shooters unless you're a professional gamer or reviewer.
Photoshop: The color accuracy is also more than adequate for my (non-professional) graphics work in Photoshop CS4. I don't do 3d, so I can't comment on that.
Conclusion: Dell UltraSharp U2412M is the best monitor in its price range for me, and I'm definitely not regretting purchasing one. After I get my new rig together, this monitor will top it off nicely. I would recommend this monitor if you like gaming and graphics designing on a non-professional basis.