Microsoft is unveiling Windows Mobile 6 in Barcelona next week, but let me just say for the record I'm pretty happy with my current Windows Mobile 5 + Flash Lite combo.
I'm an "open faced phone" kinda guy (no clam-shells please, although the Cingular 3125 is the same phone but the clamshell form factor for anyone who prefers that), and I need a phone that syncs with my Outlook client to keep track of meetings and keep me on time.
Full browser capability is also a must, and running Flash Lite is a requirement too.
An abundance of 3rd party apps is a must, as is a form factor that isn't the size of a shoe (fits very nicely in my hand or on my waist), and isn't the weight or width of a large brick are all good too.
Of course, quad-band GSM and the ability to unlock the phone to use 3rd-party GSM SIMS is also a must, since I don't like paying $200/min for roaming charges from various parts of the world when calling local (and I like being able to use my own phone with my own phonebook, Outlook client, etc when in other countries).
Anyway, I've been using the Cingular 2125 with Windows Mobile 5 for some time now and I'm pretty happy with it.
The Cingular 2125
Made by the company HTC, the Cingular 2125 is a really very good design and form factor, and Windows Mobile 5 runs very well on it. I added a 2GB min-SD storage card, which holds the 20-30 or so 3rd party apps I have installed on it + data and the essential music from my iPod's "workout" play list.
Overall, I'm pretty happy with it. Will I jump to iPhone? I'll look at it, but without Outlook sync, 3rd party app development or Flash, the excitement begins to fade. But, yeah, I'll take a look for sure.
Here's are a few screen shots of my phone, including one of the phone running a Flash Lite app (Omega Media's Wine Steward) in this case, my favorite app, where I learned about how good 2003 red Bordeaux's really are. :)
You can download Adobe Flash Lite 2.1 for Windows Mobile 5 from the Adobe website here: http://www.adobe.com/devnet/devices/index.html?tab:downloads=1.
Hopefully this is helpful to someone out there who may have similar requirements.