Accelerating its move into online delivery of film rentals, Netflixannounced Tuesday that it will soon offer about 300 films in high definitionthat can be streamed through Microsoft's Xbox 360 game console and the $100settop box being produced by Roku. In order to access the films online,customers must also subscribe to Netflix's regular mail-delivery program.Some analysts have pointed out, however, that high-definition delivered viabroadband is a far cry from high-definition delivered via Blu-ray disc.