Yes, it is valid HTML. Any element that can contain text doesn't necessarily need text.
Edit: You should note that not all browsers can find them, however. An excerpt from the HTML4 recommendation (scroll up a little bit in the document to see it in green text):
Note. User agents should be able to find anchors created by empty A elements, but some fail to do so. For example, some user agents may not find the "empty-anchor" in the following HTML fragment:
<A name="empty-anchor"></A>
<EM>...some HTML...</EM>
<A href="#empty-anchor">Link to empty anchor</A>
Last edited by rpgfan3233; 11-24-2008 at 06:30 AM.
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