I like the 'purchased <month day, year>' info. Maybe add retail (ie not bought on Steam) vs bought on Steam?
Sometimes I find myself going. Wait, where did I get that from again?
I suppose with the keys it's technically activated on X date since you can always hold off on adding the keys for a while.
Yeah it's basically just pulling the information from the "Store Transactions" tab at https://store.steamp...ed.com/account/
Then matching the title and pulling the date from that row. Again this would be nice if Valve would implement this, as I'm sure they have this info and it would be super easy for them to do. Some stuff won't work, for example the Humble Bundle keys etc. Some stuff activated elsewhere *should* work, as it'll be taking out the common terms like "comp", "retail", etc.
I also wish Steam separated multiple purchases on that page instead of lumping them together. Otherwise (if purchased on Steam) I could put "Purchased Oct 5, 2012 for $14.99" but since I purchased it along with a few other items, it would incorrectly say "Purchased on Oct 5, 2012 for $23.99".... oh Valve...
EDIT: Also, you and Spoony will be happy to know that I finally got it working to where your owned games will highlight on your wishlist page, making them easy to identify and remove.