Problem #1:
I noticed a problem with the gallery insertion code that prevents strict XHTML web sites from validating and was hoping it could be fixed in an upcoming release. WordPress has been supportive of standards based design and this error seems like a small oversight.
The problem exists because in strict XHTML, internal style sheets may only be used in the <head> of a document.
<style type="text/css">
.gallery{margin: auto;}
.gallery-item{float: left;margin-top: 10px;text-align: center;width: 33%;}
.gallery img{border: 2px solid #cfcfcf;}
.gallery-caption{margin-left: 0px;}
</style>
Whenever a Gallery is inserted automatically into a post though, it inserts this code into the site as well - into the body of the document.
The fix is to remove the code insertion and stick it into the style sheet itself. The problem is that the insertion code is buried in:
/wp-includes/media.php
It is not inside of the wp-content/themes directory which makes it likely that users would rewrite over this code anyway when updating. This insertion code should not exist in its current form.
Problem #2:
When inserting an image into a post using WordPress's "Add Media" functionality the code that it inserts into the post includes width and height attribute which do not validate in strict XHTML design.
This could easily be fixed by instead inserting:
style="width: #;height: #;"
These two issues seem like quick fixes to me that were probably just missed along the way to releasing a fabulous blog platform as quickly as possible. I hope that someone might be able to take the time to quickly fix these in a future version.
Thanks!