Some time ago I was looking at the psdev wiki and I found this:
https://www.psdevwiki.com/ps3/Keys#TMDB_Key
and it was itching in my mind for a while, as I wanted to implement it in one of my homebrews... so I did a quick coding session this morning, and added it to PKGi.
Now, for example, when you select "Details" on an item, the app will take the content_ID, generate the sha1 hmac and will try to download the ICON0.PNG directly from the TMDB. It will then show it on the "details" dialog window.
Also, when you download an item, if the icon is available it will be used for the package bubble, instead of the generic "PKGi" icon.
btw, since I was coding a bit, I added the XMB callbacks so now you can close PKGI properly using the PS button and selecting "quit" from the XMB.
I'll try to clean up the code so I can release a new version soon
PS: I was also thinking about official content updates... perhaps PKGi could query the official database, get the update XML file for the Title_ID and also queue the .pkg updates.

It will be an improvement even over the original XMB updates, because in this case they could be queued for background download, instead of blocking your PS3 until the download+update completes.
(of course, the updates would be queued in order (e.g. v1.01 , v1.05, v1.12), but the user must be wise and install them in order, or the content will become corrupt.)