Google will be changing the way it handles Sub Domains some time in the near future. The article link below isn't 100% accurate on how Google will handle the future changes. But stay tuned for a post from Matt Cutts in the next week or two discussing more about what Google's plans are on the issue.

seroundtable.com/archives/0156 ...

Official Blog googleblog.blogspot.com/2007/1 ...

hebbet, I don't think SiteLinks are the same thing as what the article was implying by sub domain handling being altered soon.

...even though sitelinks could compensate some of the missing results.

"Official" response – turns out it wasn't such a big change to begin with, that Matt was partly misunderstood:

mattcutts.com/blog/subdomains- ...