[glenstein]

I think it would be nifty to treat it as if it were a specialized form of embedded media like pictures and videos. Wall of text as a media type, and maybe even support links to, say, pastebin-type sites (or don't, this parts not critical). Then you still have tweets as the basic unit of Twitter and preserve some consistency.

[digi_owl]

Look up Twitlonger. Various clients have that built in, and it basically but the first few words in the tweet alongside a link to the full text.

[riffic]

Look up OStatus. I don't know why people place all their eggs in one walled-garden basket.

[digi_owl]

Network effect, basically.

Everyone is on Twitter, therefore everyone is on Twitter.