I'm very happy with LR5, but there are a couple of small things I would love to see added.
1. In Develop module, when syncing development settings across images, I would like the History (left-side panel) to actually list what settings where sync'ed. Right now it just says "Synchronize Settings." Maybe have the individually synced settings listed indented under "Synchronize Settings." I'd also like to see this implemented for the "Apply During Import" "Develop Settings." In my opinion, listing "Synchronize Settings" in the history panel doesn't tell me anything and can make it difficult to figure out what was applied with the sync versus what was applied otherwise.
2. If exporting files to be editing in another application (e.g. Nik or OnOne, etc), it'd be great if the exported file name could be tailored for each program. Instead of just appending "-edit" at the end, I'd like to have LR append unique identifiers based on the program it was exported to. When the external editing it done, and the file is automatically imported back into LR, I would love if the History panel told me what program the image was imported from, rather than just "Import (date & time).
3. My dream addition to LR6 would be for the program to be opened up for third-party modules. For example, a Nik Software module (along side Library, Develop, Map) that could include all their products and enable non-destructive editing. I think Jeff Schewe mentioned this as something he wanted during one of the LuLu LR video tutorials.
No matter what, I'm looking forward to seeing what Adobe does with v6.
Cheers,
Jeff