[code_duck]

I suppose you hadn't read Digg very often in 2008-2009. It mainly consisted of marketer-promoted stories, and kids posting ASCII Picards and one line, monosyllabic comments in response to these stories. The sense of community was much lower than on sites like Reddit.

Twitter is actually doing a great job of blocking spam - I used to get a few spam followers a week, now it's rare.

I follow a lot of programmers and project leaders on Twitter and your analysis, as well as the one above, are dead wrong. I constantly hear about news and see good links on twitter hours or days before they show up on places like HN or Reddit.