Just for fun, check out this link and tell me if you can find a site that is not DNN out of the 13,000 listed:

http://www.google.com/search?hl=en&rlz=1T4GGIH_en___US207&q=allinurl%3A%22Default.aspx%3Fbase%22&btnG=Search

Call me a geek, but this is really interesting.  I just checked that link again today and the total is now at 13,600 instead of an even 13K.  Not a scientific measurement, but pretty impressive since it is only counting DNN 4.5.3 or greater sites.

I'll have to watch this to see if it keeps growing like that over the next few days.

I do not disagree that the fact that the change has inadvertently made it easy to find sites that use DNN.  The issue I have the way use the new URL to find the sites was posted on a public forum.  IMO, this google search should not have been posted here if this really is a security issue and should have been reported to the DNN secuirity department according to the security policy (http://www.dotnetnuke.com/Community/SecurityPolicy/tabid/940/Default.aspx).  This would have brought this to the attention of the DNN security team members and they could have evaluated it and prioritized it accordingly.

Is the search a hard thing to do that only technical savvy user would be able to do, the answer is no.  Did posting the search URL make it easier for non-technical and technical people to be able to get a list of all DNN sites, the answer is Yes.  Is this a really big security risk, the answer is I do not know but if there are any questions it is better to be safe and report these types of thing to the securiy group instead of on the public forums.