One of the things to keep in mind about the list vs. just slap the anchors in a single container approach, is the grammar of it.
Anchors do NOT change the grammar/meaning of what they are around. It might be saying “yes this is an anchor” – but if I made the sentence:
My most recent retroGame, Paku Paku is a classic DOS game written in [url=http://en.wikipedia.org/wiki/Turbo_Pascal]Turbo Pascal. I have managed to make it available online using the [url=http://jdosbox.sourceforge.net/]Java Port of DosBox.
The presence of links in the above paragraph does not change the meaning of it’s sentences… It’s all just CDATA and it makes sense links or no…
Now, as a single sentence/phrase/paragraph does:
Sign In Create an Account Build Your Profile
Make any sense at all? that’s what just slapping anchors in there with no block level containers around them does.
NOT that I would be using IMG tags for those – it makes hover states harder, doesn’t gracefully degrade, etc, etc… That’s what image replacement is for.
Oh, and I’d also stop opening and closing php every line and make that all a single echo statement – gah that drives me nutters; but I’m the whackjob who wants to see <?php and ?> COMPLETELY REMOVED from the PHP specification.
If I was writing that same section of markup, it would probably end up thus:
echo '
<ul>
<li class="signIn">
<a href="',WEB_ROOT,'sign_in.php">
Sign In
</a>
</li><li class="createAccount">
<a href="',WEB_ROOT,'create_account.php">
Create an Account
</a>
</li><li class="buildProfile">
<a href="',WEB_ROOT,'create_profile.php">
Build Your Profile
</a>
</li>
</ul>';
Everything else handled in the CSS.