i have to say, some of the FUD thats going around about how bad this is it quite amazing, some of the issues that have been reported are just not there unless you actively go out of your way to make it like that. which is a little odd way of doing things if you ask me.
So far ive not had any issues on a desktop with old and new programs, there are a lot of metro app issues that need sorted out but hopefully that will come with development.
As it stands, is it useable? absolutely providing you take in to account a couple of things, i dont like the lack of start button in desktop mode, and for the life of me i cant see why they couldnt enable that start menu on desktop, it is after all decades of development on previous versions, Im still finding it hard getting around the OS but that should come with time. They have taken the People Hub from Windows phone and made a right mess out of it, but again, ive passed that feedback back and how it can be improved so hopefully if others do the same rather than uninstall it after 10 min and give nothing back, this may get fixed.
I honestly cant see anything that makes it unusable, but lack of start menu and thus desktop clutter will get to me on desktop mode.There are also some driver issues which isnt really Microsofts fault
You can customize the tiles quite well, but i want people groups like in WP7.
Music, pics and vids all integrated very well, tried a few apps on the app store which installed without issue and they look pretty funky. My programs from Win 7 have all installed without any issues at all. Which isnt supprising given that windows IS STILL THERE!
The only thing that i can see is definitely going to piss some folk off is the lack of start menu in desktop mode, everything else is all there and better / quicker than before! you dont need to leave desktop if you dont want too and metro is there if you need it for a snap shot of your live tiles.
Im going to hazard a guess that many of the folk complaining about this havent used it, or removed it before they gave it a chance.
One thing i will say is that this is going to create a lot of training issues in the workplace, it is all there but its not always easy to work it out when you first start, this i can see being a big issue
So there you have it, several small issues and 2 big ones.
If it had media centre on it id continue to use it everyday but alas it doesnt so that isnt an option but i shall continue to use this as much as possible because i think thats the only way to get used to it, and once again, IF its like WP7, once i do get the hang of it i will probably end up liking it
use the feedback option folks, dont just moan about it, actually contribute something and be the beta tester that you ASKED to be :)