In previous versions there was a date on when a book was added or updated to your library, where is that information in version 10?
NB.Mick — Edited
It's still there in the library (details view), you may need to right click on the column header line [green box in screenshot] and select the last update date [blue box in screenshot - note the entries appear in your selection order, I often keep last updated as the leftmost column] to instruct the library to show that particular column.
