Two interesting developments.

One is the launch of a UK venture called Unbound.

The other is the news that Amazon appears to be serious about getting into the publishing game.

In a series of public moves, Amazon.com has signaled its determination to enter the book publishing business, a move with broad implications for the online retailer as well as the traditional publishing industry.

Seattle-based Amazon in recent weeks has rolled out two new book imprints, announced a roster of best-selling authors whose books will be published under those imprints, and hired a prominent publishing executive to set up an office in New York.

The stakes are enormous. Amazon is moving more aggressively into a mature industry that posted $14 billion in sales for the United States alone in 2009, according to Simba Information, a market research firm based in Rockville, Md. The sector has been dominated for years by six publishing houses, mostly based in either New York or London.

Amazon is likely to encounter plenty of resistance, especially from established publishing houses. Many are owned by larger corporations with deep pockets. They have durable business relationships and strong brand identities that will make them difficult to dislodge.

But Amazon brings its own strengths to the table. The company is innovative and profitable, with an enormous amount of information about its customers and their preferences. Its online business model makes Amazon a tough competitor on price.