Looking at the comments, looks like there are two different requests :
1 - Adding time to the date for a task (4:00PM).
2 - Adding on Time + Effort needed to perform a task, like done in some other GTD tools. So you can pick one task knowing (if you have only 15mn for instance)

I vote for both actually :-)

Setting time to a "TO DO" would be a great enhancement. Phone calls that need to made etc.

Need this! :)

I find I add time to my task, would love this to link to a schedule and calendar

Like the program but if it is not possible to set a time for appointments will be buying one which does.

I would be using GID if it had times. ... A bizarre and extraordinarily large omission.

Along with Time it would be nice to have a "Reminder" that a time sensitive tasks is coming due soon - such as a popup reminder, an email, a text message, etc.

This is something that I continually have to go back and use Outlook for when it would be nice to have all tasks in GID.

Time + effort would be good. However, isn't importance already covered by dragging and dropping to reorder? If I want to give an action higher priority I just drag it higher in the list.

In reply to Richard - not just resource time. Time that the task should occur is far more important.

Just resource time for how long it should take to do the task.

Time would be very useful when combined with the repeat scheduling as well as what others have said below - e.g. being able to say "walk my dogs 4pm every day" would be great.

The importance grade is also critical, perhaps with different colours for the different grades.

Yes, tag the tasks in the order you want to do them, and make it easier to move them by just clicking and dragging them on mobile applications.

Not just time and importance, but effort level. Users should be able to turn off the fields if they don't want to use them.

So that you could tag todays taskes in the order that you want to do them