Siri does not have an apl, which means that developers cannot port Siri features into their apps. So the answer for now is no.
The API is being exposed in iOS 6
It's possible, but we don't know for sure. I'd like a voice command thing to close apps.So then they can possibly close down apps in 6?
Apps can be opened by voice command, through Siri, but have to be manually closed.well i think it will sure close the app if the app contains that feature for closing app through voice commands.
Manually closing apps often can be a serious drain on system resources and should only be utilized for misbehaving apps. When you manually close an app, that app must restart "from scratch" the next time it is launched. I feel it is best to avoid manually closing apps and let the system do the housekeeping. Perhaps this is why the API doesn't include such functionality.
My apologies, when I see the phrase "closing apps" I automatically think someone is talking about going into the task manager on closing them out one at a time - which is not a good practice.I agree, but I was under the impression were talking about closing apps, not clearing them from RAM. You know, by pressing the Home button. As you say, the vast majority of the time this is all that needs to be does; at least on newer iPads with 1GB or more of RAM.
Terminology is such a pain.
My apologies, when I see the phrase "closing apps" I automatically think someone is talking about going into the task manager on closing them out one at a time - which is not a good practice.
This "closing apps" assumption is a bad habit on my part, one which I should probably get rid of.