I have started to investigate this I'm thinking that as an initial implementation we
could allow you to schedule MobileCast to download all available podcasts at a
certain time of day ideally when its sitting powered on, in its cradle and connected
via wifi. 

Just to add.. on my windows mobile 5 device I use NewsBreak RSS and it as global and individual feed options 
to 
1. Dictate how many podcast should it download/keep per feed (1, 2, 3. If set to 1 it will delete the previous 
podcast to make room for the new one, etc...)
2. Specify if it should auto download the podcast or just alert you that a new podcast is available.
3. Specify the interval it will check/refresh the feed (every hour, every 6hr, every 12hrs, ever 24hr etc..)

I am hoping automation like this could be made in mobilecast as I find this feature in my current phone great 
as I dont have to do a thing and it will just download the podcast for later listening.

2 & 3 are on the radar... #1 is a separate enhancement. I'll create a ticket for that.

Definitely have it so the user can initiate the refresh / download all.  I use the
ipod touch in my car, and when I pull in the garage I'd like to hit a button that
would start all the downloads before it sleeps.  A timed method wouldn't work for me
unless it actually wakes up the ipod first.  

Make sure in any auto-download mode, it doesn't re-download a previously
played/deleted item.

Today I hit refresh, then I try to figure out where new episodes are available. In
the current version, what is the best way to get them all downloaded?  Do you have to
go feed by feed and click download?