lets see. here are the relevant entries from Wiktionary (if you don't agree with them, you can change them!):
skeptic - Noun - http://en.wiktionary.org/wiki/skeptic
- Someone undecided as to what is true.
- Someone who habitually doubts accepted beliefs and claims presented by others, requiring strong evidence before accepting any belief or claim.
denier - Noun - http://en.wiktionary.org/wiki/denial
- Someone who denies something.
see, the obvious difference here is that a skeptic needs evidence before changing their mind. a denier simply doesn't change their mind.
If you are an alcoholic, and I say "you're addicted" your responses might be "I don't think so, what makes you think that?" or "I don't believe you, prove it to me". that would be skepticism. It implies that you are open to debate, open to new information, and, importantly, open to changing your views, thoughts, and beliefs.
if, on the other hand, you simply said "no I'm not" without listening to the reasoning behind my statement, you would be in denial.
and that's where the current "debate on climate change" lies, as it relates to whether it is happening or not (oh dear, I just thought of one of the most horrible puns ever: "climate change, weather it's happening or not"). there are those who believe that it's happening fast, those that believe it is happening slowly, and those that are in complete denial. there are no more climate change skeptics. if there are, it's only because they haven't had a chance to read all the evidence that's available out there.
so if you're still a little skeptical, have a bit more of a read. climate science sites such as http://www.realclimate.org, and http://www.ipcc.ch are a great place to start. If you come across someone claiming to be a climate skeptic, check their references. make sure they are up to date too, because as far as I know there has been no new evidence to contradict the climate change hypothesis (evidence, not proof) since Roy Spencer and John Christy re-adjusted their satellite datareading in late 2005 (exact date?) ( http://en.wikipedia.org/wiki/Satellite_temperature_measurements#The_satellite_temperature_record )
happy climate denier hunting!