Demand for Sony's next-generation Playstation 3 game-console may be slowing as a recent retail check shows that systems are staying on more shelves for longer periods.

Research analyst Michael Savner of Bank of America said on Thursday that sales of the PS3 console were sluggish despite much improved availability.

Sayner found 78 percent of the 50 retailers he surveyed had the console in stock, with 70 percent saying inventory was lasting at least a week.

The results echo similar research released earlier this week from American Technology Research, indicating that 58 percent of 150 of the retailers in its checks had the system available. In contrast, only 3 percent had Sony's rival, Nintendo Wii in stock.

New video-game consoles are usually in low-supply during the first few months after the product is released. PS3’s relatively high availability since its launch in November of 2006 may be a sign of weakening demand. In comparison, rival Microsoft, which introduced its latest Xbox 360 in late 2005, saw low inventories well into January.

But at the time, Microsoft's game console cost $299 for the standard version, and $399 for a console with internal storage. Playstation’s consoles, in contrast, range between $499 to $599.

Of the retail stores surveyed, Savner found that the PS3’s high price and lack of compelling software were cited as most common reason units were left on store shelves.

In an effort to make more compelling titles, Sony announced on Wednesday that it is forming a new game studio with with Japanese software maker Namco Bandai.

Sony says it has sold 2 million Playstation 3 game systems as of the end of last week, 2 weeks later than it anticipated.