This should work. Also, I replace the msg with an echo.

Example:
<@I> http://www.youtube.com/watch?v=0_EFdod4YDo test
[YouTube]: By: eaglerocktv | (uploaded on May 29, 2008) | Title: ZZ Top - Sharp Dressed Man | Views: 3,104,757 | Rating: 5.0 (4,771 ratings)

;// YouTube Detector Identifiers //
alias -l addmark { return $+($sock($1).mark,$chr($3),$2) }

;// YouTube Detector Text Event //
on *:text:*youtube.com/watch?v=*:#: {
  if (!$sock(youtube)) {
    noop $regex($strip($1-),http:\/\/.*youtube.*\/watch\?v=(.{11})&?.*)
    sockopen youtube www.youtube.com 80 | sockmark youtube $+(#,>,$regml(1))
  }
}

;// YouTube Detector Socket (Video Information) //
on *:sockopen:youtube: {
  sockwrite -n $sockname GET $+(/watch?v=,$gettok($sock(youtube).mark,2,62)) HTTP/1.0
  sockwrite -n $sockname Host: www.youtube.com
  sockwrite -n $sockname $crlf
}
on *:sockread:youtube: {
  var %yt | sockread %yt
  if ($regex(%yt,<h1 >(.+)<\/h1>)) sockmark youtube $addmark(youtube,Title: $+(,$regml(1),),62) 
  ;if ($regex(%yt,<title>YouTube\s-\s(.+)<\/title>)) sockmark youtube $addmark(youtube,Title: $+(,$regml(1),),62)
  elseif ($regex(%yt,.+"l":\s(\d+))) sockmark youtube $addmark(youtube,Duration: $+(,$duration($regml(1)),),62)
  elseif ($regex(%yt,/ratingL-(.+)"\stitle|"smallText">(.+)\sratings<\/span>/g)) sockmark youtube $addmark(youtube,$+($regml(1),>,$regml(2)),62)
  elseif ($regex(%yt,count">(.+)<\/span>\sviews)) sockmark youtube $addmark(youtube,$regml(1),62)
  elseif ($regex(%yt,date">(.+)<\/span>)) sockmark youtube $addmark(youtube,$+($chr(40),uploaded on $regml(1),$chr(41)),62)
  elseif ($regex(%yt,<a\sclass="url"\shref="\/user\/(\w+)")) sockmark youtube $addmark(youtube,By: $+(,$regml(1),),62)
}
on *:sockclose:youtube: {
  tokenize 62 $sock(youtube).mark | var %x $numtok($sock(youtube).mark,62)
  echo -t # $1 [1,0You0,4Tube]: $iif(%x >= 7,$4 $chr(124) $5 $chr(124) $3 $chr(124) Views: $+(,$iif(%x == 7,$7,$8),) $chr(124) Rating: $iif(%x == 8,$6 $+($chr(40),$7 $iif($7 == 1,rating,ratings),$chr(41),),$+(,Ratings were disabled,)),Either the video doesn't exist or it contained a malformed video ID.)
}