The code below on 1.9 works fine in a HTML block, but if I copy this code into a Moodle 2.0 HTML block it doesn't work.
src="http://feeds.delicious.com/v2/js/tags/digitalmedia?
title=My%20Delicious%20Tags&icon&count=100&sort=alpha&flow=cloud&name&showadd&color=73ad
ff-3274d0&size=12-35">
which code?
I am sure I posted code in 
Delicious Cloud
If the script below does not show then it has been cleaned out - it is the code generated from the http://delicious.com/help/tagrolls
src="http://feeds.delicious.com/v2/js/tags/digitalmedia?
title=My%20Delicious%20Tags&icon&count=100&sort=alpha&flow=cloud&name&showadd&color=73ad
ff-3274d0&size=12-35">
Delicious Cloud
If the script below does not show then it has been cleaned out - it is the code generated from the http://delicious.com/help/tagrolls
src="http://feeds.delicious.com/v2/js/tags/digitalmedia?
title=My%20Delicious%20Tags&icon&count=100&sort=alpha&flow=cloud&name&showadd&color=73ad
ff-3274d0&size=12-35">
It is a script with a link to this external source.
<script type="text/javascript"
src="http://feeds.delicious.com/v2/js/tags/digitalmedia?
title=My%20Delicious%20Tags&icon&count=100&sort=alpha&flow=cloud&name&showadd&color=73ad
ff-3274d0&size=12-35"></script>
<script type="text/javascript"
src="http://feeds.delicious.com/v2/js/tags/digitalmedia?
title=My%20Delicious%20Tags&icon&count=100&sort=alpha&flow=cloud&name&showadd&color=73ad
ff-3274d0&size=12-35"></script>