A lot of folks are talking about this one (for a more graphical representation and a trend see here), and some choose to strongly object.
The main issue at hand is that XSS vulns (or cross-site scripting vulnerabilities) overtook buffer overflows as the most common type of reported (important to note!) vulnerability: "XSS has become the number 1 vulnerability of all time [...] in CVE" and further "Buffer overflows were number 1 year after year, but that changed in 2005 with the rise of vulnerabilities that are found in webapplications, including XSS and SQL injection."
So the objections are centered around reported vs exploited vulnerabilities as well as their relative risk.
I think some correlation is in order. For instance, look at this piece that was published at about the same time as the above research. It covers Top 5 Causes Of Credit Card Data Loss and - surprise, surprise! (not :-)) - SQL injection and other web app vulnerabilities hold a respectable #4 on the list. Now you see that this baby is not about reporting, ease of discovery, triviality and other bla-bla-bla related to web vulnerabilities; this is about losing real cash(well, credit cards, really) and getting their behinds whooped due to PCI ....