I like the new 300 seconds wait system (well, the idea is what I like). It's good against abusing. However, when I like someone and I changed my mind in the first seconds (so I want to unlike it again), it will say I have to wait 300 seconds either.
Also, when I enter a new page, the 300 seconds are away, so here it will not be effective at all.
The real thing they need to fix is to be actually be able to open the Like panel at all. Cause so far the arrow takes me to the top ... where it's pointing anyways.