Would easily be abused though by annoying people like gwynedd who will go beg on chat for people to like/recommend his posts or guys like Glue who have 7 accounts to like his own stuff.

There's a current idea in the works for something like this that has been discussed a bit by the staff.  Here's an excerpt from a post I made in the fmod forum, addressing Zarf:

----- begin excerpt -----
I think a good solution for the problem you describe would be to implement the "consensus" style point system I spoke to you about awhile ago.  For those who don't know what it is, it would be a system in which anybody could mark a post with a handful of pre-defined "tags".

So let's take the example above.  Flint makes a post that Zarf likes, so Zarf clicks "+Good" or something to that extent.  Other players can also do this, so even if Genesis doesn't necessarily agree, the power to dictate post (and therefore forum user) "reputation" lies within the community as a whole.

So now, instead of mods or forum mods having to manually award points, players can instead be rewarded in some programmatic way.  As a (rough) example, every month the top "good" poster in each forum can receive 3 tag points, the top 2nd can receive 2, the top 3rd can receive 1, etc.  The top forum users board-wide can also receive additional points in this manner.  The frequency of this could be adjusted to weekly, monthly, or even daily.  If this means tag points get given out too frequently, all we have to do is adjust the rank scale to account for it.

On the flipside, this same system can be used to expose problem posters as those where multiple users mark their posts as "bad".  This would help the forum mods know where to look for issues.

We'd be solving 2 problems at once and on top of that we'd be giving players a reason to "compete" for post points, which would be incentive to be more thoughtful in the forums, which would have an overall positive impact.

We could even give leaders the ability to see good/bad lists for posters in their family forums, to help them identify VL material and/or spot troublemakers as the round goes on.
----- end excerpt -----

Up until now we haven't spoke much about this idea publicly but we're not necessarily hiding it either.  Now that chomp is bringing it up, might as well let you guys know about it.

But yeah, chomp's on the money.  Some kind of way for players themselves to publicly rate eachothers' posts seems like a good thing.  Regarding abuse, which Zarf also mentioned:

----- begin excerpt -----
There are other details that might address your concerns.  The first being a simple one: don't allow users to vote on their own posts.  There would be no ability to reward themselves, justified or not.  As for punishing opposition, the actual power to "punish" people based on negative votes will still be something only forum mods can do, so there's no change here either.

If we were talking about a system where players could say, collectively ban another player for disagreeing with something, then yes that would be bad.  Or if say, players could make multiple threads and posts and repeatedly upvote themselves to get tag points, then yes that would be bad as well.  However, neither of those would be something that this system allows.  It won't be incredibly easy for people to unjustifiably reward themselves or punish opposition because it won't be possible for them to do either at all.
----- end excerpt -----