where people can do @'s for experiments/projects/tasks and even comparisons ...

ohhh I like that! for me this throws me directly to Slack integration .
I think my main question is, "is the discussion ephemeral?" in other words, is this an on going discussion that later no one will care about, or are we creating some "knowledge base" that we want to later share?

Also, by "address bar at the top", i assume you mean address url right?

yes... apologies for the phrasing, it was way to verbatim 😉