It's not every week that we see seminal films released in the new high-def formats, Blu-ray Disc and HD DVD. Today high-def early adopters get a bonus, with three big-ticket releases hitting on the same day. Buena Vista Home Entertainment has released the first two instalments in its Pirate of the Caribbean trilogy on Blu-ray Disc, while Warner Bros. Home Entertainment has launched two versions of The Matrix trilogy on HD DVD. Disney's content is exclusive to Blu-ray Disc; Warner says there will be a Blu-ray version of The Matrix, but not until later this year.

REVIEW OF COMBINED BLU-RAY/HD DVD DRIVE

All three films began shipping today - and all have made auspicious debuts in the US, if their respective sales rankings on Amazon.com are any indication. The rankings are not a scientific indicator of sales or popularity of one format over the other: Amazon.com represents only a microcosm of the overall retail market, and its sales rankings include both shipping titles and pre-orders. Amazon's sales rankings can be easily manipulated, too - back in April, a group of HD DVD devotees on the AV Science Forum banded together to buy HD DVD discs at Amazon on the same day, an effort which resulted in a temporary spike in HD DVD sales.

At 11 AM Pacific Time yesterday, Dead Man's Chest and The Curse of the Black Pearl (the second and first Pirates films) were ranked 8th and 9th among all films sold on DVD, Blu-ray, and HD DVD on Amazon.com. Each disc was priced at $23.95.

The Matrix films were a bit further back. The Ultimate Matrix Collection on HD DVD (price: $73.95), which includes a bonus disc, is at 15 (only one other HD DVD title is higher, Planet Earth: The Complete BBC Series, at number 10). And The Complete Matrix Trilogy (price: $63.95) is back at number 24.