I played around on the site for the last hour after signing up and already see some things I'd like to see on here even though I think this site is pretty awesome.
The only real reason I keep my games in a spreadsheet is so I don't end up with duplicates (which has happened to me several times when I see a vintage game at a thrift store, etc. that I didn't think I already owned).
Also, I tend to organize my games by Genre, and then in chronological order (or basically, "however I feel like it") LOL...
I keep all "Star Wars" games together regardless of Genre or platform — Grand Theft takes a special place on my mantle (my favorites of all time) — and I have pretty much every console version of the Call of Duty / Medal of Honor series along with all other military FPS shooters, then any OTHER fps shooters in the same place, but "space" ones together (like Halo) etc etc.
I don't really have a set system.
It would be really awesome if there were other sorting options for viewing your collection, such as by genre (instead of just platform / alpha).
The "completely awesome" thing to do would be to allow users to have a "my bookshelf" option for a list view, and allow them to manually sort their collection to their liking. Maybe even "groups" to allow users to categorize their own sub-collections.
I could see a sweet ajax list where users could drag their titles in the order they want (like put the GTA titles in the order they were made vs alphabetical). It probably wouldn't be terribly difficult to implement by adding a "group" and "priority" field to the collection table for each user in the database. Grouped games would be able to be dragged as a unit. Could use checkboxes to drag multiple games around etc.
Just ideas. I can see myself using this site to organize my collection — but I do have them in a google spreadsheet and on my bookshelves in a certain way that makes them easier for me to see the genres and collections I have "holes" in to fill.
However, my simple spreadsheet is getting to be a pain because of how big my collection is starting to get.