- Where's your privacy policy detailed? With the nature of the service (gathering email addresses etc) you could head-off lots of questions with that.
- A default serif font drags anything down. For me personally I'd prefer another font.
- You sensibly replace emails, but other links like 'unsubscribe' remain intact, which could be problematic (don't worry, you'll still get your costco emails although it can sometimes lead to real emails/names).
- I guess grouping and parsing is the next step, i.e. process them and provide features around them a la tripit. Is that the direction you might take it?