1. Users can manually review each item before it's published or set up certain substreams that do different things - like automatically publish my iTunes transactions but ask me before publishing my Amazon purchases. Kaplan has two credit cards, one with a Blippy sticker on it to remind him that purchases made with that card are posted immediately to the web.

2. It's not about the money. Kaplan says he wants Blippy to be a way for offline activity to publish online conversation. The things you buy are often convenient signals for activities that are important to you. The conversations that go on around the items are quite interesting... at least on Kaplan's profile. He can buy a movie on iTunes and find a conversation about it swarming around his automatic Blippy post before the opening previews are over. Other users often don't see any comments on their activity at all. Jason Calacanis sees some good conversation.

3. Blippy now sees $2 million worth of user transactions streaming through the site per week, Kaplan says, and has seen close to $15 million in transactions total since it launched publicly January 15.

4. Kaplan doesn't think sharing credit card data is that big a deal. He cites LinkedIn founder Reid Hoffman's argument that people will share anything if there's enough of a benefit to sharing it. Friendster was the first site where people used their real names on the Internet, and people weren't comfortable with that at first, either.

5. Data portability: Kaplan is working on a Blippy App Programming Interface and "it's going to have everything." Data caching policy is something "we have to think about still." Imagine a website that recommends recipes based on the food it knows you have in your refridgerator. That's one example of the kind of service that could be built on top of Blippy.

6. Aggregate data analysis isn't something Kaplan is personally interested in, he says. It's hard to believe but he says he'll leave that kind of thing up to third parties using the Blippy API if they want to. The company will focus all its energy on making Blippy a good experiene for users. Really, that's what he said.

7. Location data is something Blippy sees but doesn't expose right now. Kaplan says it's coming, though. He thinks the current location-based social networks need to deliver more value to users, and says that's something Blippy can do.

People these days produce all kinds of data streams, Kaplan says - from Facebook to Twitter to Smart Grid utility use and electronic medical data. Some of those streams you wouldn't want to be public about at all, but some of them you can benefit from partially exposing. He thinks that at least some of your credit card transactions are better shared than kept private. Time will tell whether or not other people agree with him.