For those of us who have been on the Macside all along, it might help to explain what features you're looking for. Presumably something that isn't in TextEdit (the current Mac-default text editor). Rarely use it myself, so I don't know what's missing. Lot of people use BBEdit or TextWrangler. I do almost everything in SubEthaEdit because it's multilingual w/r/t line endings and text encoding, and has "modes" for the common programming languages. I've only used css, js and of course html myself and it always thinks my Error logs are in Lasso (?!) because of the leading bracket ;), but there are about 30 built-ins.
depends on exactly what's important to you. For free ones, try jedit, komodo, etc not sure if netbeans is free, but some people like it. eclipse is a fully featured IDE, but be aware that it needs a lot of memory to run. Personally, I like Coda, or Espresso
Really, comes down to a personal preference - most of these can be configured to suit you.