Well, its in the title. What about when someone clicks on your profile, and it shows when they were last online? it should look like this: Last sign in:[month/day/year/(time?)]
(this might have been suggested before, but oh well)
The problem with the Last User Online was partly the site's fault. This has no where near the capacity for features as AG3 will have, since AG3 will be coded completely from scratch. Actually, the whole reason for AG3 was because of the site's capacity. Seemingly-good features just made the whole site slow.
We've already discussed this several times. Short answer: yes, we'll have an "is online" and "was last online ..." areas on the user's profiles (or maybe also when you hover over a user's armatar).
And for those who don't want people to see it, you'll have ways to make yourself "invisible" when on the site.
Well, to clear up the confusion of "it says they're offline, but they're posting?!" we might omit the "offline" tag, and only show something if they're online and want to show it.