It has only been a couple hours since the official announcement of the Dell Axim X50 lineup, but there are already quite a few reviews out on the enthusiast sites. It looks like Dell has the right idea and supports the enthusiast community in addition to the big media sites and here is a roundup of reviews. Since the devices won't be shipping to buyers until November, it is valuable to check out as many reviews as you can so you can read differing opinions and help make your own judgement since you can't touch and feel the devices in retail stores. Feel free to post links to other reviews as they come online. I know Jason Dunn is working on his X50v review that should be posted soon too.
X50v
Aximsite
PDAGeek.com
pocketnow.com
PDA Buyer's Guide
BargainPDA.com
infoSync World
Brighthand
PDA Gold
X50 Mid-Level
Aximsite
PDAGeek.com (Chris said I could put this shameless plug here:))
Pocket PC Thoughts
pocketnow.com
infoSync World
X50 Entry-Level
infoSync World