I was just looking at the walkthrough of Windows Phone OS (http://intruders.tv/inqtv/2009/07/31/windows-phone-os-walkthrough/).

Some remarks:

First of all, as usual, Microsoft has started his copier-machines and copied about everything of the iPhone OS and Android OS, but just not well enough.

I don’t like the mix of two kinds of user-interfaces: the Zune layout and the icon layout. Stick to one of them (neither one of them is great, I must say), that might solve a lot of disappointment for the end-user.
The iPhone OS is icon-layout based, but at least you can put the icons on different screens, so you can organize them in logic categories. In Microsoft Phone OS it’s one big list, not very practical.

Then the browser. Of course it’s IE and it seems to be very slow! The remark of the Microsoft rep is ridiculous: “there’s a lot of people here” isn’t a good reason. Also no multi-touch, so you can’t zoom in and out on an article. Not practical in my opinion!
The support of Flash is something we have seen in the HTC Hero phone, that’s running on Android OS, so actually, that’s nothing new.

Then the “new” app Microsoft Tag. How idiot can you be to try to invent a new kind of tagging system?! What’s wrong with the old one, everybody knows and uses.
- “Guys, we have to make an ad-campaign for a large company, and we have to put tags on them.”
- “Do we have to support Microsoft Phone users also?”
- “Of course”
- “So that means: two different websites and two different tags for the ads. That will cost a lot of money and time!”

Now, one more thing: if you’re about to give a demo of a mobile phone, make sure that everything is installed and configured properly, so you don’t get the annoying messages like “Would you like to import all your contacts?”.