I just got the MyTouch 3G and love it...it does have its pros and cons, though.
Hardware:
The screen- is nice and large, bright, very responsive touch screen.
Physical buttons- has a volume rocker on the side which is nice, would have loved to see a dedicated camera button the on the side to launch the camera/video recorder and take the pictures. Has home, menu, back, search , send and end buttons which all are pretty nice, only sometimes the back button doesn't have the user experience I would like. Such as when you open an application and it automatically opens the page you were last on, and when I hit back to get back in the app it actually takes you back to the initial page you were on, and this only occurs sometimes, so its inconsistent in that way.
ports- the charger and headphone jack are in the same port and it is one usb port. Hate them being in the same location, but T-Mobile does provide an adapter for a 3.5mm headset from the mini usb port.
Trackball-is pretty smooth, lights up when your phone is woken up, ie receiving a text message or an email etc.
Status lights- Not too bright or too big just the right size
Camera-takes great pictures, only doesn't have a flash, which is a downgrade from my old phone, the LED flashes are small, but def came in handy.
Speaker- Nice quality, can hear while walking outside with traffic driving by.
Size- of the phone is not too big, good size to fit in my hand thin enough to fit in a pocket
Storage- It is under the battery cover, but you can replace it without taking out the battery which is great!
Battery- Died pretty quick the first few days, but now it holds a charge through the day and maybe longer depending on what I use my phone for during the day.
Talking on the device- Can hear when on a call loud and clear, but the device does pick up a little too much of the background noise.
Software:
Android (cupcake)- Nice OS, especially since it is open source, allows for lots of great development.
Gmail- Works seamlessly with the device. Wish I could see different label colors, but it does the job.
Homescreen-love the ability to add widgets, downloaded all sorts of apps and placed the widgets on the homescreen, would love to have more homescreen space though (can be accomplished by downloading other themes)
onscreen keyboard- it takes a little getting used to after ditching my physical QWERTY, but it really helps to have the keyboard suggest words you are typing and auto correct common misspelled words. I don't like how the numbers are on a totally separate screen. Sometimes when selecting a text entry field to being typing, my keyboard lags in popping up. I recently downloaded the HTC keyboard and now use that as my default on screen keyboard.
Voice search- Always recognizes what I say! Works perfect, haven't had a problem yet. Starts up pretty quickly and searches Google pretty fast. This is a great tool.
portrait to landscape- very smooth animations and transition when using the accelerometer to switch to a different mode.
gallery- Great folders to view different options of images. Don't like the default way of browsing images.
Camera- wish camera had more settings, but you can download apps to accomplish this.
Market- Tons of apps out there to customize your device.
contacts- The default contact application needs some work. The phone imports all of your contacts from gmail and you end up with a long list of contacts. Must download an app from the market to have a better user experience.
messaging- Like the threaded view and the integration of sms and mms together.
Notification bar- Nifty thing to have, like that you can customize if you would like to receive notifications for certain things.
profiles- hate that I can't have my phone vibrate when I receive an sms, its either sound or silent :/ otherwise can customize ringtones and what not which is pretty common.
wifi- works pretty well, connects to open networks fast, lets you decide if you would like to be notified of an open network, can also set up vpn. Connects and detects networks pretty fast.
Love that you can have apps running in the background, just have to make sure to kill apps you don't want running as to not slow down the processor, games run pretty smoothly only had trouble with guitar hero because it uses a lot of processor speed and I had too many apps open at once.
T-Mobile network:
Recently traveled to salt lake city and Atlanta and didn't have any problems getting 3G speeds. LA has great 3G speeds as well. I love the fact that I can browse the net while talking on speaker phone.
GPS- Using cell towers is pretty inaccurate, especially being that T-Mobile doesn't have many 3G cell towers in certain areas. Satellite is extremely accurate, always pinpoints me in the correct spot.
All n all I'd say its a pretty solid device...I love it and still have much more to explore, I learn a new trick everyday ^_^
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