Save yourself some trouble with iLife'11
Just for testing it I installed the new iLife'11 on one of my systems. I mostly use iPhoto and I was happy with iLife'09. What I can see now is that iPhoto look has changed to be more similar to iMovie on the user interface. Some floating menus (like photo adjustment) are not embedded on the application window and general look is worse IMHO.
But this is not the only problem. Calendars are no longer available on iPhoto, so it seems they will be back soon.
The worst thing, however, happened when I was using the new iPhoto: Suddenly my system stopped responding to mouse click or keyboard. Pointer still moved with the mouse but that was it. I suspend the system and when restarted I've just got a blue screen. I power it off by holding the power button for a few seconds. On the next power up they system asked me if I wanted to send a report to Apple, which I did.
Whether this was caused by the new version of iLife or not, I do not know. But my system has been running rock solid for several months, so I'd guess iLife'11 is the more likely cause.
The bad news is that you cannot easily go back, to the former version of iLife as your photo library has been converted to a new format. Apple: this is just insane. I'm not sure I want to use time machine to go back in time to get this as it was before (not sure if it will work nicely).
So my advice with iLife'11 is for you to refrain from updating till Apple irons out all the wrinkles of this release. I'm sorry I'm not mentioning other programs of the suite, like Garage Band that I guess has got an important face-lift, but it is not a program I use.
Update: A few days ago I've got a software upgrade for iPhoto'11. Since I reported my machine hanging once while using the new iPhoto I've got not the same problem again.