I mentioned this in Europe this week, and as others have blogged it I thought that I should mention it directly myself. My public facing sites (http://www.forta.com http://www.cffaq.com and others) are running on Blackstone, and have been since early alpha days. I did not mention this until now because I wanted to see if users would comment on any problems or issues, and none have. While I have definitely found bugs in some of the new Blackstone features, core CF (pre Blackstone functionality) has been running perfectly, not an error, and no problems logged. As a matter of fact, I have even been updating the server every few days with newer product builds (yes, server updates, on a live production box) and so far so good. Blackstone, now in beta, is essentially ColdFusion MX 6.1 with new stuff added to it, which means that core CF is for the most part unchanged. All indications are that they CFMX.x to Blackstone migration, when the product finally ships, should be one of the most painless ColdFusion upgrades ever.