[General] Updated Hub usage metric - PPD perspective

[Jared Rhine]

>> It seems like lots of the above is useful info for Hub users too.   
>> Do you mean to collect the above specifically for Desktop users,  
>> split off?  I'm guessing it might wind up being difficult to split  
>> the two categories even; for something like # of editors, we might  
>> wind up with an aggregate of both Desktop and Hub users making  
>> edits on an item.
>
> I think it's important to distinguish between Desktop and Hub users.  
> I'd like to work towards understanding if there are any qualitative  
> differences between the way Desktop and Hub-only users use Chandler.

Ok.  I'm ok with trying to break Hub users up into these buckets of  
"Desktop User" and "Hub User".  We still need to get to a shared  
understanding of what defines these buckets.

Top questions for me:

- Are there really 2 buckets or 3?  Is every one of the 4,000 odd  
users get tagged (somehow) as *either* a Desktop User *or* Hub User?   
Or 3 buckets: "Desktop User", "Hub User", or "both"?

_ If those are the only buckets, then what if the only client used by  
a user if iCal or Lightning or Evolution?

- What characterizes a Desktop user?  Is it "if the user has ever sent  
a request to the server which has their username via Desktop"?  (If  
they sync their Desktop to Hub, I'll see them with a "user agent" of  
"Chandler/*" with their actual username, unless they used a ticket (in  
which case I don't know who they are)).

I'm not (yet) saying there's a good, distinct way to sort each user  
into these buckets.  Without these buckets, answering a question like  
"average number of edits per day of Desktop Users vs number of edits  
per day of Hub-UI users" will be difficult.  Once we determine we can  
sort users into these buckets, then we face the question of whether we  
can feasibly extract a metric like "number of edits per day" now or  
need additional backend support.

-- Jared