Amazing job! Thanks for doing it.
I was getting troubled on reestarting bashpodder when stopping it without
letting it complete its cicle.  It d get lots of already downloaded stuff,
cause the temp file was not incorporated to the main log.
U see, I live in an area with frequent thunderstorms, so I have to unplug my
computer in order to avoid a fried mainboard. (That's right, I have to unplug
it!!)
So I moved the posision of the "# Move dynamically created log file to
permanent log file:" bit to the top. Now it incorporates the temp file first,
get rid of it, and then start to look for new stuff.
It sounds like this, what do u think?:

#!/bin/bash
# By Linc 10/1/2004
# Find the latest script at http://linc.homeunix.org:8080/scripts/bashpodder
# Last revision 07/01/2005 - Many Contributers!
# If you use this and have made improvements or have comments
# drop me an email at linc dot fessenden at gmail dot com
# I'd appreciate it!

# Move dynamically created log file to permanent log file:
cat podcast.log >> temp.log
sort temp.log | uniq > podcast.log
rm temp.log

# Make script crontab friendly:
cd $(dirname $0)

# datadir is the directory you want podcasts saved to:
datadir=$(date +%Y-%m-%d)

# Check for and create datadir if necessary:
if test ! -d $datadir
       then
       mkdir $datadir
fi

# Delete any temp file:
rm -f temp.log

# Read the bp.conf file and wget any url not already in the podcast.log file:
while read podcast
       do
       file=$(wget -q $podcast -O - | xsltproc parse_enclosure.xsl - 2> /dev/null)
|| file=$(wget -q $podcast -O - | tr '\r' '\n' | tr \' \" | sed -n
's/.*url="\([^"]*\)".*/\1/p')
       for url in $file
               do
               if ! grep "$url" podcast.log > /dev/null
                       then
                       wget -q -P $datadir "$url" && echo $url >> temp.log
               fi
               done
       done < bp.conf

# Create an m3u playlist:
ls $datadir | grep -v m3u > $datadir/podcast.m3u

Anyway, congratulations for this amazing stuff!