Although nice, the new subtype feature is a bit of a con, IMO.
It allows me to sort tasks (or other objects) by subtype, but not by the fields and fields values each subtype entails.
Basically the custom fields are kept as useless as before.
A practical example.
For all the subtypes I have define there are some common fields we have defined long ago, like Task Status, which is a select list with values like "acknowledged, processing, waiting on customer" and so forth.
I am still unable to sort tasks by these values. This is where the real juice is.