I am unsure about some of the implications of this switch, but here are my thoughts
1) OS X - it is the first reason I use a mac. I will NEVER go back to windows.
1b) Coming a VERY close second - Apple design. It rocks. I will never buy a beige or black box. New apple books may have intel processors, but they will also have superior design, hinges, wireless antennas built-in, stunningly clean lines with sexy white and silver (yes, I love white and I love silver), decent port placement and single button trackpads
. All the things we take for granted than you have to PAY EXTRA for in a pc laptop.
2) Apple as a complete package - from the colour of the keyboard to the hardware support, Apple products are whole.
3) Cheaper macs - leading to more macs, leading to a happier world
and with faster bug fixes (growls at ichat 3, dvd burning and crappy tiger uptimes)
4) Apple using intel technology to push new ideas and get ahead of the market - shaping the world to apple design and ease of use values
1) The risk of OS X for x86 leaking out. I assume Apple has this covered (see above posts on motherboard ROMs and so forth) but its a risk
2) Misinformation! The lack of detail in the keynote hasnt helped
3) Possibility of getting screwed over again - slow delivery times, better processors to competitors
4) Intel insider stickers... BARF! Hopefully apple design rules will never allow this idea to surface!!
OK there is heaps more good and bad but i can't take it all in at once, dammit!