Simple Answers:
Like: Layout, smoothness.
Dislike: Can't register an app to have the wide images that you see in MS Start menu entries, can't make changes at run time, too few strips, (possibly) too few items per strip, no user notification when a strip gets 'bumped' off.
Detailed Answers:
Mostly, I'd be re-iterating my previous ideas about strips.
I'm writing Addinistrator at the moment, so I'll offer all of the ideas I've had about it.
In a perfect world, I think that there should be an unlimited number of Start menu strips, but that work be done on CONSOLODATING those strips, to prevent the start menu being cluttered. And users should have control of those strips within Media Center.
Grouping
For example, I'd like the users to be able to 'groups' of addins (with addins coming with their own default groups, based on the category they are installed in - ie. Pictures, TV, Movies, Games etc.). You could then have a single strip (or more than 1) devoted to a single Group. For example, you could have a 'Games' strip that shows the programs installed in that category.
They should be sorted by FREQUENCY OF USE, rather than by the date of installation
Consolidation
As the strips become crowded, I think the Start menu strips should 'collapse'. So let's say a user has a Media Center Flash Jukebox, EMUCenter and another game addin (such as GameEx) installed into the 'Games' group. And while they don't currently, let's assume that these applications all have their own strips and have MULTIPLE start menu items on each of their strips.
You could effectively 'collapse' these applications by putting all of their seperate options in a sub-menu (like a 'More With This' menu), so the only three items that would actually appear in the Start menu would be 'EMUCenter', 'GameEx' and 'Media Center Flash Jukebox'...all of the detail would be able to be 'drilled down' to when you choose the application.
This would IDEALLY be done as an overlay over the start menu, but to make things easier on the dev team, a completely seperate sub-menu would also be fine.
Context
Additionally, I think applications should have the ability to edit their own (and ONLY their own) Start menu strip. This way, if a user does have a Start menu strip devoted to a single application (for example, Yougle, Big Screen Headlines or EMUCenter), their favourite or most used SUB ITEMS from that addin (eg. YouTube for Yougle, your favourite RSS feed in Headlines, the last played game in EMUCenter etc.) could be made available as an entry in the start menu strip.
Customisation
When an application with a new Start menu entry is registered and Media Center is started (or notified) then a dialog should appear asking me if I want to add it to my Start menu. It should ideally have three options, 'Yes', 'No' and 'More' (or something similar) to allow me to either add it automatically, refuse to add it, or go straight to the interface that allows me to group my addins and choose which Start menu strips appear.
Look and Feel
With the square images that you can register with Media Center, it's impossible to make our Start menu entries look as good as the wide-aspect images used by Microsoft in their start menu entries. Custom start menu entries should be able to display wide images.
Start Menus, Ordering & Default Focus
OK, the third one is stolen from emigratings good idea. I think that from the registration XML file, it should be possible to...
Create a Start Menu Strip (optional - the registry option isn't too bad, but still can cause 32/64 bit installer issues)
Specify the ORDER of the items in the Start Menu strip (VERY important!)
Specify which item should get the default focus
ALL of these functions are the sort of requests I've had from users, so I know they have a real, legitimate use and that users do want them - or they are from me, because of workarounds and problems I've had.
100 downloads a day for Yougle Vista - goin' allright!
Check out http://www.thedigitallifestyle.com/cs/Blogs/developer/default.aspx and http://www.push-a-button.com.au/products/mce