Thank you for the review. Yes I changed the text that shows up on "text thumbnails" in the last version. Before it was a combination of domain/subdomain, now it's the title of the bookmark. The reason was that on ad-hoc bookmarks that I sometimes add it was difficult to say which link was which. E.g. if you create bookmarks to let's say 2 of your emails in gmail - before the change - the thumbs would look exactly the same. Now they should contain the title (so the title of the emails) so they should be different.
There is, however, some room for improvement - like you mentioned - cropping the text that appears on a thumb should be helpful, as very long titles do look weird. That is something that will be fixed soon.