Rumors that Amazon wants to acquire Netflix have cropped up a couple times over the past year. Now they're making the rounds again, after the Wall Street Journal's Deal Journal wrote that "Netflix is becoming a lot more attractive to Amazon." The reason? Netflix's success with building its streaming video business. The DVD-rental company recently said 48 percent of its customers watched more than 15 minutes of a streaming TV episode or movie in the fourth quarter, up from 28 percent in the same period a year ago.

Deal Journal quotes Collins Stewart analyst Sandeep Aggarwal as saying "There is now even a higher possibility’’ of an Amazon-Netflix deal. Amazon has struggled to establish its own on-demand video service, which is a key part of its overall digital strategy along with its Kindle and MP3 offerings.

Not everyone is convinced, however. Motley Fool is already trying to debunk the rumor mill, arguing that a) the Amazon and Netflix cultures don't necessarily mesh, b) acquiring Netflix would require Amazon to collect sales tax in more states, and c) that a deal wouldn't make sense if Amazon isn't interested in the Netflix physical DVD business.

The sales tax issue may be a factor, given that Amazon has vigorously fought efforts by various cash-strapped states to make it collect sales tax this past year. At the same time, if Netflix succeeds in making itself a streaming video powerhouse, the company could help Amazon beef up its digital efforts with TV and movies.

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