Comparison shopping and Blue Nile (NILE)

Quick question: Since comparison shopping puts price pressure on broad e-commerce retailers like Amazon, will we see a similar phenomenon with online jewelry retailers like Blue Nile?

Observation: A number of specialized comparison shopping engines, such as PriceScope,
have sprung up with specific focus on diamonds. Also, the broad
comparison shopping engines like Shopping.com, Nextag, Shopzilla and
Yahoo! Shopping are getting better
at covering niche markets like diamond engagement rings.

The online
jewelry retailers are trying to build brand and raise their gross
margins. But comparison shopping engines reduce the value of brands and
compress the margins of all the players in a space.

Stock impact: As PriceScope and
sites like it attract more users, that's probably incrementally negative for Blue
Nile.

Chart for NILE below.

Full disclosure: at the time of writing I'm long SHOP.