After facing down Blockbuster and Wal-Mart, the online DVD-rental company may be an acquisition target -- but it won't go for cheap It's the oldest plot in the movies: Upstart takes on the champ, wins a few rounds, gets his nose bloodied, then gets back up and wins the fight. Rocky X? Not this time. It's the story of online DVD-rental pioneer Netflix (NFLX ), whose stock is still flirting with a 52-week high set last month as its competition withers. Speculation is building that some rival will decide that, if it can't beat Netflix, it needs to buy the...