Sort of a style note: ```temp``` is not really a very descriptive variable name. >.> Also, I'd shorten the line a bit by doing
```blurb_cache_key = (is_author_of?(bookmark) ? "bookmark-owner-blurb-#{bookmark.cache_key}" : "bookmark-blurb-#{bookmark.cache_key}")```

(Some people would even shorten it as
```blurb_cache_key = "bookmark-#{(is_author_of?(bookmark) ? "owner-" : "")}blurb-#{bookmark.cache_key}"```
I'm not sure if that's readable enough to justify the space-saving. ;) )