Often these problems arise because the web sites themselves have not upgraded their pages to account for the changes in the new versions of browsers.
if you are having problems, you can always revert back to IE8 and wait for Yahoo to fix the problems.
However I'm sure Yahoo has a comprehensive and thriving community of their own. Have you searched their own forums for similar reported problems?
after i started using ie9,i noticed yahoo.com doesnt always load the slideshow thing for the news headlines on the front page.most times all it shows is the first four,and it doesnt cycle through,just stays on that one article.and the preview on my yahoo buttons dont always work either.but when one works,so does the other.and its impossible for me to comment on engadget or ign.and it can be difficult to change pages with the comments on ign.is there a problem that requires an update?
i use chrome as my backup browser,but i like the way ie9 is setup.very streamlined,it looks nice,and if these problems could be fixed,it would be perfect for me.anyone having the same problem?or ideas?