Overall good, and the patois transliterations (the "spell it as it's pronounced" parts) work very well with my generic eastern Canadian dialect. Could use a few more words, though — I think there are more than 240 that are either unique to the creole or at least different in usage from Standard English
And I'd consider adding a few pages/notes on the grammar as well as the site grows (things like how you form a question and put things into the past or future tense, which are different from Standard English). Creoles like Jamaican Patois are very interesting languages, and I think that people who are interested in the words would also be interested in how they are put together.
The colour differences work in the call-out (word of the day) box, but they don't really do it for the main column. Against the grey background pattern, it's hard to see the difference between the green <em> elements and the black text of the <dd> elements. I'd suggest either making the <em> elements bolder or indenting the definition an em or two, then using a negative margin-left to "outdent" the <em> elements.
Another thing I've noticed, and it maybe just because of my development background, is that I can't make JP "automatically" stand for Jamaican Patois in my mind. JP is the language code (and the country code) for Japan, and it hurts my brain to force it to stand for patois several times on a page. It's a minor violation of the "don't make me think" rule; I'd have just used "patois" (or even P/PAT).
Major congratulations are in order, though, for not trying to make the site look like a Rastafied Jamaican flag. Not to put too fine a point on it, but when I've worked on projects for Jamaican-Canadian clients in the past — people with very respectable, up-market businesses — both in print and on the web, by the time it's "Jamaican enough" for the client it looks like a bad flyer for an amateur Bob Marley tribute band's free concert in the park (and while I take the money, I don't put it in my portfolio, and I feel kind of dirty). Nice to see somebody celebrating culture without pandering to the tourist tee-shirt trade.