iPhoto is very slow

So I'm wondering if iPhoto is actually working normally for anyone?

I have 50Gb photo library and it's just soooo slooooooow. Yesterday instantly upon opening it fired up 80% CPU usage. I have the latest iPhoto and ML and.... even latest Mac Mini. So I would understand if it sucks on older Macs, but on latest hardware. Yes the Mini is not the most powerful, but they could easily simplify iPhoto and make it work. Actually, I had iMac, pretty powerful hackintosh and iPhoto always sucked on them too. I like iPhoto very much, but it just doesn't work...

So does your iPhoto work fine, like it seems during Apple's keynotes, or do you agree that it is the worstly optimized app?

Any suggestions for preferably cheap or free alternatives? I just can't stand it anymore :/ And if I switch to an alternative, will I have to sort all my photos again (which would be crazy amount of work)?