I love my Windows Phone!
Greetings Windows Phone Users!!
a) what are the strengths / weaknesses from your point of view of these devices
I like the ease of use in the newer Windows Phone 6.5.x OS, as well as the compatibility and easy/full integration with my Windows-based desktops, whether at work or home. I also like the high availability of QUALITY apps and the idea that they'll eventually be available in a single location (Windows Marketplace). Even though other devices are claiming victory, there "upgrades" are centered around being more of an enterprise device (like Windows Phone).
The primary weakness is Microsoft's old paradigm of the Windows Mobile device as primarily a business device. Because of such, I think they assumed each device would be supported by an IT person. However, I do see Microsoft shifting away from this kind of thinking.
b) what are your views on where Windows Mobile is now (as a platform, both WM itself and with HTC doing their layering stuff on top)
The platform is slowly making the shift from the business world paradigm to a consumer-based paradigm. Things that used to require the specific help of an IT person are becoming more automated and easier to use.
As far as HTC, they are providing value to what they create. In the same way, there are still many other skinning programs available that do just as much or more than HTC does. Just the same, its great to get some of HTC's advanced functions "out of the box."
As a side note - I wish Phone Carriers would be restricted from adding their BLOATWARE to these phones and slowing down many of these fine devices and OS to snail speed. By removing the bloatware, many Windows Phones show a very significant improvement in performance.
c) where do think Windows Phones are going? what do you want to see next?
I think they're going in the right direction, however, I'd like to see an earlier release of Windows Mobile 7 than 4th Quarter 2010. Again, I'd also like to see greater controls on the Phone Carriers. They should not be allowed to load their Bloatware and "cripple" these wonderful Windows Phone devices.
d) what do you think BlackBerry users would immediately like about Windows phones? what would be gain? what we lose (other than BlackBerry Messenger!)
I think you'd enjoy the ease of use of the e-mail system, texting and you'll enjoy the larger keyboards on the keyboard equipped devices. If you go for a non-touch device, I think you'll be wishing for that hardware keyboard. Personally, I don't want to give up any screen "real estate" for a screen-based keyboard.
Also, I think you'd give up multiple calendars. I'd like to see Windows upgrade to allow for multiple calendar integration.
e) how's the app situation? how's the game situation? quantity and quality, where would you rank them in the smartphone space?
I think this is an area where Windows Phone really excels. There is such a great range of products to choose from and they're not "cheesy" like many of the iPhone apps I've seen. Not only do they consistently work, but most developers provide ongoing support without milking you dry (unlike their Windows desktop counterparts). I've been using Windows CE since version 2.11 and have always found excellent apps that consistently perform as good or better than expected.
Also, since most of these developers create out of their passion for these devices, they really create awe inspiring apps that do more and their not modularly developed to be sold piece-by-piece.
Gaming is pretty good too ... plenty of Arcade action (Guitar Hero, Tetris, PacMan, Bubble Breaker, Space Invaders, Asteroids, Narnia: Prince Caspian, Midnight Pool, Lunar Tilt, Block Breaker, etc.), Board games (Monopoly, Scrabble, etc.), Action Games (Call of Duty, Need for Speed, Eagle Eye, Spiderman, Anthelion, etc.), Card Games (Solitaire, Hearts, UNO, Texas Hold 'Em, Spades, Phase 10, etc.), Brain games (Big Kahuna Words, Brain Up, Puzzle Quest, etc.) and plenty more. Yes, I actually own all of these and many more.
f) I'd just like to get some stories from all the hardcore users here about how you use/integrate your device into your daily life.
Easy enough ... you have the obvious uses like e-mail, text messages, Facebook, Twitter and Internet surfing. Working in the IT Department, my Windows Phone device also helps me on the go. I can create, modify and close Help Desk tickets on the go using Spiceworks' Tickets Anywhere (and its free too). I can provide Remote Desktop support, ping Internet devices, SSH into servers, etc. I also use GPS, WiFi and WiFiFoFum to track down "rogue" wireless routers in our office building.
And then there's things like weather apps, free GPS-enabled apps like Google Maps, amAze, Waze, GCZII and others. I like to use the speech-enabled search engines like Bing for when I'm on the go in the car ... as well as Voice Commander for controlling my Windows Phone device while driving (phone calls, "reading" appointments, tasks, playing media through my car stereo system, etc.). While I'm not one to wear a bluetooth headset everywhere I go, I do use it extensively in the car, so I can keep my Safe Driver discount!
I also like to use the Internet when I'm shopping to do live price comparisons ... this helps me cut down on bad impulse buys and also investigate sales pitches!

Its funny to watch the face of a salesman when they ask what you're doing and you tell them you're Googling what they just told you.
I could go on and on, but I'm going to finish this rave talking about how much I love having a camera at my disposal, especially having a 16 month old child. I can always capture those special moments via pic or video ... quick, easy and at a high resolution too! Then, I can use my phone as a digital display to show off those special moments, or upload to Facebook or Twitter.
P.S. And my phone (HTC Fuze/Raphael) is pretty indestructible too. When my 16 month old gets too rowdy or "wiggly" while shopping, I can activate her playlist on Mobile Media Player, lock the phone and hand it to her ... and she will be calm and happy ... that's priceless!!!!