I like this unit so much that even though there are a bunch of reviews out on the internet I decided to write my own anyways. Not going to be terribly long just going to go point by point.
Screen - The screen on this display is gorgeous. Sure it's not VGA like some people would like but QVGA is pretty damn nice. The landscape mode that WM2003SE supports is nice to have as well especially for browsing webpages. Good screen sensitivity makes for easy handwriting recognition.
Size & weight - After having my larger UR There @migo I was suprised at how small this unit is especially with what's packed into it hardware wise. Very thin along with being nice & light are a combo that I like having in a Pocket PC. It doesn't feel super rugged but that's what my RhinoSkin aluminum case is for
Speed - This model has the latest & greatest Intel XScale processor running at 624 Mhz although some people have successfuly overclocked it to over 700 Mhz. It has good response speed and I have seen a noticeable improvement in terms of speed over my 206 Mhz StrongARM equipped Amigo.
Sound - The built in speaker on this unit is adequate at best but the audio is great when you plug in a set of headphones. Folks that want to use this unit to play a lot of mp3 files or what have you would probably use headphones anyways so it's not a big deal.
Connectivity - This unit has both bluetooth & 802.11b built into the unit. Both of which work very well out of the box and are easy to configure. I don't personally have any bluetooth devices yet but it detected and worked with my friends' phones just fine. I was able to tap into my home wireless network easily out of the box.
Storage - This unit comes with 64 megs of RAM and 64 megs of ROM which is a good amount. It also has an SD card slot although some X5 owners might miss not having a CF slot. Not a big deal for me really even though I already have a few CF cards I'll just use them for my digital camera. So with the built in memory and a 256 meg SD card I'm pretty good to go although I can get larger cards if I want. Memory speed in terms of read & right is pretty fast although I haven't benchmarked it as of yet.
Software - The unit comes with pretty much the default setup you'd expect to see in Windows Mobile edition. Pocket Excel and Pocket word are in there as usual along with the normal Outlook applications. I'm not sure if this is only on the Dell or if it normally comes with Windows Mobile 2003 SE but I really do like the backup application that's included. It's nothing super fancy but made things a lot easier with my replacement unit. The unit I had received had a slight defect on the screen that was only visible in certain lighting conditions. Considering how much I paid for the unit though I wanted a replacement. I got the replacement (pretty darn quickly too) and it was a simple matter of popping in the SD card with the backup file in it, selecting restore and it transferred all of my files & settings in a matter of about a minute and a half.
Overall this is a great PDA and an improvement over my previous PDA. I'm going to be enjoying this unit for a long time to come and recommend it to anybody looking to upgrade or to get a new PDA.