Does Thunderstone offer a web-site personalization solution?

Yes, but note that "personalization" is used to describe many kinds of functionality. At the simplest level, you may store user preferences, so that each user receives only desired information when visiting the site. To accomplish this, Texis can recognize users by login or cookie, and it provides a mechanism for carrying a user's identity from page to page in an encrypted format, so that preferences may be taken into account on every page visited. Personalization sometimes refers to a more elaborate process of capturing user actions (such as purchases or even individual clicks) on an ongoing basis, and using that information to influence what is displayed to the user subsequently. Such logic could be implemented in Texis but is not provided as a finished solution.