It looks like you can select it under your profile settings. I selected my day and time and my time zone so it seems to now be showing when posts occured
Personally, I don't. But I believe it's supposed to be an automatic thing... if you get booted off suddenly, the system now "remembers" as much of the draft as you had at last "draft saved" point, before you got the boot... when you re-load a particular thread.
I haven't really experimented with it yet because, to me, it's a pointless option.
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"Yabba Dabba Doo" - Frederick J. Flintstone... So what?
(Judd Nelson as Atty. Robin 'Stormy' Weathers in "From the Hip")