I agree iPhoto is pretty impressive, and I'm not the guy you were flaming, BUT here are a few gripes / bugs...
well first, I didn't intend to come across as flaming the user I was replying to... honestly, what bothered me is that unlike you, he/she simply made the statement that iPhoto had "BUGS!!!" and left it at that (whereas you at least went into detail about the issues you're having- which I can respect). meanwhile, there were a couple things I thought I'd mention about your issues:
1. Sending a slideshow to iDVD can't be done in PAL format.
actually, it may be because I have QuickTime Pro, but I have the option of doing a "Custom Export" from directly within iPhoto, and from there I'm able to access plenty of options for PAL export... and if you're trying to burn the slideshow directly to iDVD using the Share -> Send to iDVD route, all you have to do is go into the Preferences in iDVD and choose "PAL" under the Video Mode tab.
2a. Apple keeps changing the way photos are "shared". If you burn photos to disc using the intuitive "Share\Burn" it burns the files in iPhoto library format. Resulting in my Windows friends not being able to work out what the hell is wrong with the disc and also the morons at the photo lab printing the thumbnails.
I'm not sure where the confusion is here, since when I choose Share -> Burn, it prompts me with this: "If you want to create a disc to be viewed on a Windows computer or by a photo processing company, you must use the Burn Disc command in the Finder." seems pretty self-explanatory.
2b. Sharing the photos by email means I have to choose the photo quality / file size in iphoto and then choose it again in Mail. Why twice?
that's a good question- why, if you know it's going to prompt you twice by starting the process from iPhoto, would you not just open a new message in Mail and browse to the photo and choose the new size from there? I tried it, and it worked like a charm.
3. Slideshow music ALWAYS ends early and loops back to the start of the song on the last photo. Sounds crap.
well, this is pretty obviously bound to happen if you've picked a track that's shorter than the slideshow... it's going to try to fill the remaining space with something other than silence, so naturally it will try to work with what you've given it and restart the song from the beginning- hardly a bug by any means.
4. Not sure what the photo book quality is like in the US, but in Australia the books are expensive and they look cheap and nasty. Snapfish is cheaper and much better quality. No point having all the maps / themes in the world if in the end the print quality is rubbish.
I can't really argue this one way or the other since I've never seen an example of a photobook ordered through Apple in person (and I can't really give input here since I've never ordered one using Apple's services)... unfortunately, that's a shame that you found their photobooks to be of "rubbish" quality only after you'd ordered one, but at least you have the option of ordering them from Snapfish in the future.
needless to say, I can see where you'd be frustrated, but hopefully the ideas I threw out there were either helpful or at least gave you some food for thought... good luck either way.