Cyberghost,
Take a look at the attached chart. The bulb for the Dewalt 788 is an "intermediate" style base, circled on the chart. Any bulb with that style base will fit and work safely on your saw as long as that bulb uses no more than 25 watts. Don't concern yourself with the "Type S" labelling, what you want is the "intermediate" base. The wattage is what can cause a fire, such as using a 100w bulb in a 40w fixture. The 100w bulb would generate too much heat for the fixture to handle.
To me, a 25w bulb just isn't bright enough, so I switched the supplied 25w incandescent bulb with a 13w compact fluorescent (CFL) bulb. A 13w CFL puts out light equivalent to a 60w incandescent bulb. So, for less power consumption (13w vs. 25w) you get almost 3 times as much light. However, that still wasn't bright enough for me, so I've put two swing arm style lights over my saw, each loaded with a 23w CFL bulb putting 5000k light. The 23w CFL each put out light equivalent to a 100w incandescent bulb, and at 5000k, its nice bright, white, light. With both lights on, the table of my saw looks like an operating table! Some might not like it that bright, but I love it!
Hope this helps!