Delicious Post users take note: Due to changes introduced by yesterday's relaunch of Delicious, the Post to Delicious dialog doesn't save your tags correctly.
Until yesterday, you could specify multiple tags for a new bookmark by separating them with a space; for example, entering "aecreations extensions firefox" in the tag field would create a new bookmark with those three tags. Now, a single tag is created instead, named "aecreations extensions firefox".
A workaround to this is to separate each tag with a comma; for example, "aecreations, extensions, firefox". Spaces after the comma are allowed; they will be stripped out automatically.
A fix will be available shortly to change the instructions in the Post to Delicious dialog.
EDIT: This post has been corrected with information about spaces after the comma separating the tag names.