What's the problem with the V3 API?
===================================

In short:
- no decent support for hardware with multiple frontends
  and/or multiple MPEG decoders
- no support for special purpose recording/playback hardware
- broken semantics of demux ioctls for timeshift
- restrictive design of the dvr device

These are structural issues which are hard to fix in the
existing API, so we decided to start over and clean a lot
of stuff up:

- completely new demux and CI API
- clean namespace

There are also many extensions to the audio decoder API,
which new includes support for postprocessing and mixing.

The frontend API is unchanged, except for renamed
types and ioctls to match Linux CodingStyle rules, and
the added DVB_ prefix.

Most of this stuff is not an issue for users who just have
a PCI card in or USB device attached to their PC. But
modern set-top-box chip sets offer features which cannot
be supported with the V3 API.

For more information please refer to the discussions
in the linux-dvb mailing list archives at
http://linuxtv.org/mailinglists/linux-dvb/
(search for "V4").