[chl]

I'm pretty happy to see mutations and variations like Subjot, and, yes, even Heello to appear; Twitter seems to have become too large to do a lot of experimentation themselves (not surprising: every change of the fundamental format would have massive ramifications).

In addition to "substreams" (probably the defining feature) & comments, Subjot interestingly keeps a posting length limit (250 characters).

As Google+ demonstrates (IMVHO, of course), _some_ limit actually is a good thing in terms of scannability, "follow cost" &c.

Those newspaper folks didn't invent the lead for nothing.