Superbits are released by Sony/Columbia and I've read that the main differences are greater horizontal detail and less compression artifacts. Also all superbits have both Dolby Digital and DTS 5.1 audio tracks and, usually, no extras.
Superbits are pretty much the same in other regards as any other DVD and any benefits are likely to be more noticable on larger screens
I'll just echo Sigismund's comments along with the advice to do a search (bottom right of page) for "superbit" on this forum, there's been plenty of talk about the pro's and con's of the various titles released under the Superbit banner.
Basicly the idea behind Superbit is to have the highest quality picture and sound available on dvd, to do this they take away any extra's e.g. commentaries, documentaries, and use all the space on the disc ONLY for the film with a Dolby Digital 5.1 and DTS 5.1 soundtrack. Some titles are now being released as 2-disc sets with the extra's only going on the 2nd disc... Oh, and they play on regular dvd players.
I've only got one superbit title myself (The Fifth Element R1, aquired from Sigismund in the trade section last year ) and can highly recommend it, especially if you own a large screen plasma or projector... but, as you will no doubt read, there are titles that hardly have any noticable difference over it's "regular" retail release.
Originally posted by FoxyMulder But as has been mentioned many times the idea that Superbit uses all the disc space is a con it doesn't use all the space and some discs can have as much as 3 gigabytes of space left over.
The DVD specs that that the maximum bitrate that can be used on DVDs is 9800 kbps (kilo bits per second). Therefore a 1.5 hour movie, even if encoded at the max bitrate for the entire length would only take 6.3 GB of disc space. It is not possible to make the movie any bigger.
I don't think this can be called a con since the studios are making the disc in the best quality that DVD will allow.