I know EXACTLY what is wrong
Hi, I had the same problem with a MacBook Pro 15.4" Merom. Here's the story.
First I'll draw my conclusion: your logic board is broken and needs to be replaced.
Part I -- After 3 cycles, the battery wouldn't charge as in: if I'd pop in the MagSafe connector, the light stayed green (flickering mostly of the time). Also, I could definitely hear some weird soft high frequency noise coming out of the MagSafe connector. I returned it to the shop, got a new battery and the problem wasn't fixed.
I think you are in Part I, now what actually happened?
Part II -- Problem wasn't fixed, returned it again and was really pissed since I build pc's and maintain/fix macs myself and they came up with some **** story. However, they ordererd something called a 'Battery Assembly Kit'. It appears to be you have certain maintainable parts especially for charging the battery. They told me that it included new intern wiring and some other stuff. I got my friends MB Pro back and problem wasn't solved.
And now the solution:
Part III -- Almost killed the tech guy, but apart from that: they replaced the ENTIRE LOGIC BOARD. My Logic Board appeared to be broken. Since then, the problem is solved.