Quality Tags for Web Content

I need a standard set of adjectives for tagging content in a shared bookmarking system, particularly describing quality. No standard exists that I am aware of.

This is what I know is out there today:

• Positive: Delicious, Furl, Twitter, Facebook, Twine, NYTimes TimesPeople, IBM/Lotus Connections Dogear all assume that all links in the system are positive.
• Positive-and-Negative: Reddit, StumbleUpon, Digg have support for "voting down"
• Likert scales: Newstrust uses these for multiple categories. This is too abstract and time-consuming for most users.

Delicious and other free-tagging services get around this by letting the user supply their own tags, which may be adjectives. This is unfortunate, because quality is just the sort of metric you want to aggregate across different users. So a controlled vocabulary is desired.

This is a refinement on my ViewPoints model (2004). I had designed ViewPoints with discussion threads in mind, and made it overly didactic. ViewPoints feedback could be re-organized in terms of positive, negative, or remedial feedback. Whether you choose to give negative or remedial ratings often depends on how much you want to help the author and/or whether the author is seeking input.

I've reserved unique letters for each, as well as suggested a symbolic notation.

Positive scale
+ Interesting: Pleasant, humorous, enjoyable, or otherwise needs further
++ Helpful: Provides utility for problem solving
+++ Enlightening: Deeply informative about a given topic
++++ Fundamental: Read it now. Will change the way the way you think.

Negative scale
- Disappointing: Not very interesting
-- Unhelpful: I have no idea where I can apply this
--- Redundant: I've heard this before.
---- Troubling: Will change the way people will think, in a bad way, and should be avoided.

Remedial scale
/ Confusing: Minor flaws.
// Overwrought: Too long; could say the same with less.
/// Lacking: Missing information.
//// Poor: Needs major rework.