Optimal Resizing Workflow - iPhone, iPad, AppleTV, etc...

Question

I have an Adobe Lightroom catalog of around 60,000 hi-res TIF and RAW images, and I would like to take my favorite 5,000 or so of these images and import them into iPhoto so that I can then sync them to my iPhone, my iPad, view them on my Apple TV, upload them to Facebook, and perhaps even get some iPhoto books printed up.
I shoot with a Canon 5D MKII so the images in Lightroom are enormous. I am in search of the optimal resizing formula to use when exporting downsized JPEGs from Lightroom for subsequent import into iPhoto.
In other words I would like to figure out the perfect dimension/resolution combo to use that would ensure that my images look great on whatever device they are viewed on, and that I'll always have a large enough image to accomplish anything I might want to use iPhoto to do with them.
Specs for iDevices I would view the images on, as well as Apple's suggested minimum resolution of images for
iPhone 4 ~ 960-by-640-pixel resolution at 326 pixels per inch (ppi)
iPad ~ 1024-by-768-pixel resolution at 132 pixels per inch (ppi)
Apple TV ~ 1280-by-720-pixel resolution at 72 pixels per inch (ppi)
iPhoto Books (for the maximum 20 x 30 inches print) ~ 1600 by 2400 pixels (pixels per inch not specified here)
Anyone care to take a stab at suggesting a single 'universal' resizing formula (height/width/resolution) for optimizing my images for the above mentioned outputs? Thanks!

Answer 1

iPhone 4 ~ 960-by-640-pixel resolution at 326 pixels per inch (ppi)
iPad ~ 1024-by-768-pixel resolution at 132 pixels per inch (ppi)
That's easy: choose the longest side: Long Edge is 1024 pixels. You don't care about where is width and where is height, because both devices rotate.
Apple TV ~ 1280-by-720-pixel resolution at 72 pixels per inch (ppi)
It's easy too: Fit width 1280/height 720. You DO care for with and height, since TVs don't usually rotate.
A universal formula for above 3 devices would be to choose the largest width and height of all. That would be: fit width 1280/height 1024.
iPhoto Books (for the maximum 20 x 30 inches print) ~ 1600 by 2400 pixels (pixels per inch not specified here)
Even if they don't specify resolution, for print you need at least some 240 ppi. At 30 inch, that will be 30*240=7200 pixels. That mean you need to your images full, without any downsampling.
The final advice:
1. Use fit width 1280, height 1024.
2. Import full-size to iPhoto for books as you need them. You're not going to print all those 5000 pictures, are you?