[jandrese]

We had two versions of a particular app once. One used BeautifulSoup to parse the page and pull out the relevant elements. The other used some crusty old Regex patterns. At the end of the day the Regex version required about half of the maintenance the tag soup version did. IMHO the difference was that it took some of the content into consideration unlike the tag only version that was more sensitive to otherwise invisible changes under the hood.

[Vindicis]

Not to mention the sheer difference in performance between the two. I've found regexes to be magnitudes faster than parsers, for extracting data, that is.