As I wrote the list for what AS can and can't do for the AS guide that the list in the first post was just copied from - I will give my comments:
1) Activesync does not allow you to create partnerships with more than 2 Personal Computers.
The practicalities of syncing to more than two computers is quite difficult. AS assumes that your PDA is THE conduit between the two PC's - which makes sense. There is a freeware application available which allows you to sync to more than two PC's but each time you need to select which of the Partnerships is the 'main' one and the data from that partnership is used to sync with the current partnership. If you change a document on Partnership 1, and then another document on Partnership 2 sync'ing to partnership 3 becomes a very difficult excercise with quite a lot of user intervention - can you imagine the problems this would cause for 'newbies' and overwritten files.
2) Activesync cannot synchronize more than ONE mail account inbox.
The logistics of this is difficult to manage using the current sync'ing premise that AS uses ie) make everything the same on each computer.
I would love to have a separate account facility, and not just for the inbox. It would also be great if you could sync to a work PC and a home PC and choose which information is combined and which is kept separate. IMHO this is the main feature missing from AS.
3) Activesync is UNABLE to synchronize data with another PIM software (including Outlook Express). It can only synchronize with Outlook itself.
From a practicality position I understand this one. Writing a conduit for every piece of software out there would be almost impossible. Remember on Palms you had to use the desktop. Also MS 'gives' you Outlook which I think is better than Desktop to be able to do this.
4) Activesync can only synchronize data in the main Tasks, Contacts and Notes directories and not sub-directories.
Not sure why this feature couldn't be added fairly easily - after all you can already sync sub-directories of the inbox
5) Activesync cannot synchronize data/ files to any memory other than the main memory of your device.
This is a practicallity issue - and IMHO is taken as a 'saftey first' measure. What happens if you choose to sync to SD card and the next time you sync the card isn't in your device
6) Activesync cannot create a partnership using WIFI.
This may be due to the age of the underlying architecture within AS. I am sure at some time on the future this will be added.
I think AS does what it does very well and most users have no issues with it, but as I said I think MS has taken a 'saftey first' approach to AS, which can be annoying if you are a user who wants to have every option customisable.