Sure, titles are there to get attention and to summarize channels and items, but there's another consideration: Titles should be comprehensible out of context.
For example, the title "Not Again!!!" might grab attention, but who knows what it means? A busy person scanning RSS feeds might not want to take the time to find out. Ideally, RSS titles for both channels and items should make sense even when read out of context.
The title "New Announcement," for example, might not be as widely clicked as a title like "New Super Savers to Hawaii."
The same goes for descriptions. It always pays to write descriptions that provide some context. You don't want your readers to feel clueless as to what was intended. A little context goes a long way.
For example, define acronyms and don't refer to "this site," since your content may be aggregated and displayed on other sites.