Blippy, the new “Twitter of shopping”, is getting a lot of attention for letting you share your credit card purchases online for all to see.  What people aren’t focusing on is how Blippy shares that info: automatically.  You just give Blippy your credit card  or merchant log-in credentials and they post your purchases almost in realtime (the actual delay varies by bank).   “Passive sharing” is a game changer.

For example, wouldn’t FourSquare be better if followed Blippy’s example and automatically “checked you in” at the bar when you bought drinks with your credit card?  Another example is TripIt.  I love TripIt’s travel itinerary service in theory but they require me to forward all my flight and hotel info to TripIt’s system — which I usually forget to do.  Why doesn’t TripIt just ask for my Gmail login and then parse what it needs out of my emails coming from Expedia, the airlines, hotels, etc.?

One of TripIt’s main features is the ability to share your travel plans with friends.  However, when I flew to New York recently, my NY friends knew I was coming because they saw my Manhattan hotel reservation on Blippy, not TripIt.  Why?  Because I didn’t get around to actively sharing my itinerary with TripIt.  When building a product/service it is usually best to assume your users will be lazy.

CONTROLLING WHAT NOT TO SHARE

It will be interesting to see what controls people want when the only active decision is what not to share. For example, Blippy started with:

• the ability to turn sharing on/off per merchant or credit card
• ability hide selected purchases
• clear, prominent “delete my account” link

Recently they’ve added (presumably due to user feedback):

• ability to see what you’ve previously hidden
• permanent delete

It seems that Blippy is still figuring this out. They’ve clearly sidestepped the Facebook Beacon debacle but most Blippy users only share a small fraction of their purchases, often just iTunes and Netflix.  Perhaps people just need more time to get comfortable with Blippy before sharing more. Or, maybe it will take new controls like:

• hide purchases over $X.XX
• don’t display the price paid: always, if over $X.XX, for people I don’t follow, for purchases from selected merchants
• hide purchases containing selected keywords
• hide purchases in selected categories (ex: healthcare)

Ultimately Blippy will probably earn the most trust (and prevent the most privacy mis-steps) by proactively hiding potentially sensitive purchases and then asking you to confirm you want them public or deleted — sort of like when the credit card company calls to ask if a suspicious charge is really yours.

So, stay tuned.  If Blippy can convince mainstream consumers to share widely then other services should pay close attention to Blippy’s privacy & permissions approach.

Suppose you were trying to choose a hotel for a vacation to Hawaii. Wouldn’t it be helpful to know where your friends (and their friends) have stayed in Hawaii recently? Or, say you are about to buy an HD camcorder, wouldn’t you like to know who in your network already owns it? Well, Blippy knows.

Blippy is a new Twitter-like site that allows you to easily broadcast your purchase activity and see what your friends are buying at sites like Amazon, Zappos, iTunes, NetFlix, and more.

Blippy combines two things:

1. What are you buying?
2. Who do you know?

The result is voyeuristically amusing at first, then oddly addictive. It becomes clear that Blippy is building something really valuable: the “product graph”, a map of who owns what. You’re now six degrees of separation from a first-hand review of any product or service. Is that Maui hotel really as good as it says? Find the 3 people in your network who’ve stayed there and ask them. Are the extra features on the high-end camcorder really useful? Ask your friend who bought it last month (and see what he paid for it).

THE POWER OF PERSONAL REFERRALS
When it comes to shopping, using personal connections to help filter the internet is increasingly important for a couple reasons:

1. The Web is too crowded
Ten years ago you were lucky to find an online product review.  Today there’s simply too much information and most of it is unhelpful.  Try Googling a digital camera like the Panasonic Lumix DMC-GF1.  It has 30 million results.  The vast majority of those pages are link farms or SEO pseudo-content.  Not even Google’s famously accurate ranking algorithms can keep all the spam separated from the few trustworthy sites.

2. Online reviews are increasingly unreliable
Aggressive marketers are taking advantage of the openess of review systems, writing fake reviews, and compromising their integrity.  Consumers are noticing.

Faced with these problems, consumers are using services like Twitter and Facebook to get product recommendations from people they know and trust.  However, these services weren’t designed for this task.  Instead of blasting “What’s a good dishwasher??” to all your Twitter followers, Blippy could let you ask just those people who’ve recently bought a model that you’re considering.

The way consumers find products online and decide what to buy hasn’t improved significantly for at least 5 years. Done well, the product graph could be a breakthrough. Of course, to build a really useful product graph Blippy will need to convince millions of mainstream consumers that it’s a good idea to share their purchase information — a tricky proposition. For now at least, Blippy looks like it has a good chance at making the product graph idea a reality.