Question 1) Does the current VDR integration support having all the tuner cards in a server and then multiple clients (MDs) utilising them - as MythTV does quite well?
Yes VDR supports this but currently inside LinuxMCE this is not automatically setup for you. The options here are to configure vdr yourself to do this or to wait until we have this available in an update.
Question 2) Does VDR have the same extent of recording options as MythTV for regular recordings (things like Pad the start/end, record from any channel etc. Is the interface for this entirely within linuxMCE?
I can't compare MythTV to VDR as i dont have any experience with Myth. But I can confirm that VDR has options to allow for the padding of the start/end time of recordings, can use VPS if it is supported by your TV stations, it can record from any channel on the MUX that a tuner is tuned to concurrently. Pressing F6 while watching Live TV will bring up the UI2 EPG/Channel guide which allows you to use a fully integrated UI2 media browser like interface to 'tumble' through channels, schedules for any channel and set recordings etc. TV recordings can accessed from the Videos screen in UI2. However there are still some VDR functions, menus that must be accessed from the vdr OSD interface... in the future we plan to integrate these too into UI2.
Question 3) Particularly for Australia - Is the broadcasted EPG guide sufficient? Does it provide enough data or is it/should it/can it be suplemented with an external guide data source?
VDR supports external data sources for EPG data... but these require plugins to be added to vdr.
Question 4) Is viewing of recorded programs entirely though linuxMCE videos interface or can they be browsed/viewed through another interface? Also how does this work for programs that are still recording?
you can view recorded programs from the Videos menu screen... they will appear along side ripped DVD's and any other video content you have stored on your core. However if you playback a VDR recording from the Videos menu screen while that recording is still underway then LinuxMCE will only be able to play back that recording up to the point the recording was at when you pressed 'Play'. However if you use VDR internal Play Back capability then you can start playing a current recording and VDR will do 'chase play' while the recording continues. Also currently he only way to use 'Live Pause' is from the internal VDR OSD interface.
Question 5) Is there the equivalent of MythWeb for web based scheduling of recordings?
Yes there is and its called vdradmin-am. I have written some Wiki notes on installing and configuring vdradmin-am here; http://wiki.linuxmce.org/index.php/Vdradmin-am
Hope the above helps.