tedster - 7:07 pm on Jul 24, 2010 (gmt 0)
One "trick" not mentioned so far is to give the letters an offset drop shadow, but scale back the opacity so that it's barely noticeable. This faint shadow softens any visible pixels along the edges of the letter forms.
I prefer not to use the preset drop shadow effect. Instead I'm a bit old skool - I've been using Photoshop since version 2.
1. duplicate the text layer behind the original
2. offset that second layer, to the right and down just a bit
3. Rasterize the letters in that second layer
4. Fill with black, preserving transparency
5. Gaussian Blur to taste
6. scale back the Opacity of the shadow layer - I often end up at 30% or ever lower
7. "Save for the Web" as png 8-bit, and 16 colors is almost always all you need