Question: I'm using the Adobe CS5 suite and trying to upload all of my pictures to Facebook... and .NEF files are too large to upload, any suggestions?

Answer: 
Well, Facebook isn't going to handle NEF anyways. However, if you have CS5, that means you have Adobe Bridge and the batch functionality to perform image conversion from there. The short example would be...

1. Open bridge and find an image directory to work on.
2. Select the images to modify.
3. Select on the menu: "Tools -> Photoshop -> Image Processor"

This is going to run Photoshop. From there you will be presented with a dialog that provides a number of options for batch processing including using the first image as the basis for further changes, file type to save as, etc. You may want to experiment a little with a small set of images, but be aware that Raw conversion to JPEG is seldom, if ever really, a consistent change. 

Personally, I would never do this for final images. I've only ever done it for proof images where I've totally controlled the light used in the shoot, but for anything else, including images I intend for display on the web or in print, the editing is done image by image. This is generally because white balance changes, sharpening changes, and a host of other little tweaks that vary as a result of settings, light, and more.

By the way, if you haven't a lot of Photoshop experience with photographs, I'd recommend Scott Kelby's "[The Adobe Photoshop CS5 Book for Digital Photographers](http://rads.stackoverflow.com/amzn/click/0321703561)" as a good place to start (Google if the link doesn't work). There are a lot of other resources, but he covers a lot of ground and does it with some style, so worth the rather small price of admission.
Create a [batch process](http://www.youtube.com/watch?v=PTtWEtN06EI) to convert from .NEF to .JPEG with Photoshop. Don't forget to include closing the picture in your recording as Photoshop does have a finite limit on number of open files. This solution is ideal if you took your photos in the same lighting condition so corrections, if any, are the same. 

For corrections: at the very least, you need to reduce your file size (i.e. change dpi, dimensions) to meet Facebook's restrictions.