I just went and had a look at NoteTab, and see that the pro version has different colors for identifying tags, etc, for html, and it also has a compare files capability, but in the light version you apparently can't put the files side by side.
Have you tried this capability? I tried Beyond Compare on some else's recommendation here, and it is excellent for comparing (i.e., putting the files side by side and highlighting differences in lines laid side by side...). For the couple of times I've needed a capability of this sort, I've REALLY needed it, and I'm just wondering if you know whether Note Tab would serve as well.
Thanks - Tony