For anyone still curious about this - I notice they aren't using SSL to encrypt their website/content. (Sites that use SSL will use addresses that begin with "https://" rather than "http://")
That wasn't unusual a few years ago, but nowadays the vast majority of business websites use SSL. It makes a site much less vulnerable to all sorts of attacks designed to intercept data being sent to/from users, or to spoof the site in an attempt to distribute malware or capture customers' personal information.
Many ISPs, but not all of them, treat a lack of SSL encryption as a security threat - even if the site appears to be healthy and safe to use. This would account for some ISPs issuing warnings while others do not.
The main thing to keep in mind is NEVER to do any kind of e-commerce on a site that doesn't use SSL and have a valid certificate. (Your browser will tell you very clearly if a site is using an expired or bogus certificate.) Doing so is pretty much the equivalent of driving around with your credit card number painted on the side of your car: It's not a matter of IF somebody will take advantage, it's a matter of WHEN
