The real problem is that % signs need to be escaped, since they have a special meaning in crontab. The % signs in crontab will be changed to newline and everything after the first % sign is interpreted as standard input to the command. Therefore you crontab entry will result in:
00 1 * * 1 svnadmin dump /home/svn/collection | gzip > /media/remote/Backup/svnserver01/$(date +
and the parenthesis highlighted in red is responsible of the error. You should change the date command into:
Hope this helps.