I'm hoping this was just some sort of error from Google's Safe Browsing Web Bot service. This is the message I received when I pursued the matter:
Safe Browsing
Diagnostic page for gustavmahlerboard.com
What is the current listing status for gustavmahlerboard.com?
Site is listed as suspicious - visiting this web site may harm your computer.
Part of this site was listed for suspicious activity 1 time(s) over the past 90 days.
What happened when Google visited this site?
Of the 4 pages we tested on the site over the past 90 days, 0 page(s) resulted in malicious software being downloaded and installed without user consent. The last time Google visited this site was on 2013-12-09, and suspicious content was never found on this site within the past 90 days.This site was hosted on 1 network(s) including AS17139 (CORPCOLO).
Has this site acted as an intermediary resulting in further distribution of malware?
Over the past 90 days, gustavmahlerboard.com did not appear to function as an intermediary for the infection of any sites.
Has this site hosted malware?
No, this site has not hosted malicious software over the past 90 days.
How did this happen?
In some cases, third parties can add malicious code to legitimate sites, which would cause us to show the warning message.
Next steps:
Return to the previous page.
If you are the owner of this web site, you can request a review of your site using Google Webmaster Tools. More information about the review process is available in Google's Webmaster Help Center.
Yesterday I used Google's Webmaster Tools to request that they re-review this matter. I honestly do not know if there is an actual problem. FWIW, I did not receive the Safe Browsing message when I navigated to the site today, so perhaps the matter is resolved.