Designers must be aware of their role in social UIs and give the same thought to social dynamics that they would to legibility, scalability and others. They must be aware of what social friction they are introducing or reducing, and they need to ask themselves, “How will this UI make my user look to others?” and “How will this UI affect the quality of social interactions?”

How to present and sell design: 1) Don't wing it — postpone until you're ready. 2) Really sell your design — the idea that 'good design speaks for itself' is a myth. 3) Don't get subjective or allow your feelings to get hurt — tell them to tell you when it doesn't work. 4) Don't embarrass the client — make them look good, be honest, listen to them.

A superb guide for anyone proposing ideas to clients who challenge you in potentially frustrating ways.