I actually like Nirvana now. At the time I was totally indifferent and as you mentioned just wondered how they generated so much hype when bands like Mudhoney, Pixies etc were barely acknowledged. I remember listening to one gushing review saying they would have a bigger impact than Hendrix. Now I can just listen to them as I would like to have at the time. Just a bunch of blokes with some good tunes and a great sound.