anidb[0] is definitely larger, while not for profit.
anidb is a (truly wonderful) monster.
> 13898 Anime
The new site does seem to have more entries, but I haven't checked what the differences are exactly (e.g. are some things counted in one but not in other). For example the table shows 36 movies from 1910s, in AniDB there is only 26 (search with start time between 1.1.1910 and 1.1.1920, the only entries are movies).
The files are fansubs/rips/etc. Each file has hashes and information about container and the streams in it (codec, resolution, bitrate for video, also the language for audio and subs). Also whether the ep is censored if applicable, whether it's a dvdrip/bdrip/streamrip... a ton of information.