Hi Everyone, I've had my macbook, 13inch poly unibody for less than a year now and I use it quite a lot for school and work. Ater charging it the other day I noticed a "service battery" error which went away the next. I checked the power section in the System Utilities and I noticed that my battery has shifted from "Good" to "normal" and I'm now at 469 cycles which I do not understand.... I also notice a very quiet humming-- I'm not sure if I'm just being paranoid and searching for problems or if there's a correlation amongst the issues. I've let the battery wear it self down and shut down and sit for a few hours and fully charge which has helped, but now it only holds charge for about 3-4 hours or so, opposed to the 5 hours I got when I initially bought it. Any advice on what I can do? Should I get a new battery or try something else? I can't bare the thought of parting away from my macbook because its MY LIFE, lol. So any advice that would allow me to service it on my own would be more than appreciated. Perhaps I've overcharged it? Please help me! Thanks so much in advance my fellow mac users. Regardless of the few issues I've faced, I cannot fathom using another system after using mac.