Yahoo / Hotmail may just be temporarily deferring your email rather than rejecting it outright. That list you mentioned is good, seems to have covered most of the important stuff. You might also want to make sure your mail server's IP address is not on any of the black lists. The following is a link to a perl script intended to be run from nagios that checks the following blacklists: dnsbl.sorbs.net, list.dsbl.org, zen.spamhaus.org, fulldom.rfc-ignorant.org, bl.spamcop.net, and blackholes.mail-abuse.org

http://pastebin.ca/1694024