Ironically, the Evo actually has 2 notification lights, one on each side of the speaker mesh where your ear goes. Ironically again, the stock Sprint ROM and all based on it only use the left one (charging one). The right one was somehow found by someone and incorporated into Cyanogen.
Now, when I get a message while charging (left light is on), I can still see if I have a notification because the right one does the job.
Why, oh why, did Sprint have a phone made with 2 lights, and only use one???
PS - The lack of a notification light is ridiculous and yet another way that Samsung could further separate themselves from Apple if they'd put it back on.
To be honest, I hope this phone is the anti-iPhone, and has none of the lawsuit-prompting designs that previous Galaxy/Nexus phones have had.