I usually don't bother lubricating any of my tools. A lube really just allows little particles of dust, lint, sand etc to collect in the hinges and other crannies and cause more of a mess than they help.
Of course, if you do want or need to lubricate a tool I suggest plain old mineral oil from the local pharmacy. It's cheaper than dirt and it's food safe so you can use the tool to prepare lunch or cut your steak if you need to. If you want to get fancy, you can try a product called INOX, which is mineral oil with a penetrating compound. It's decent stuff, but costs more and I don't really know how much more of a bonus you are getting with the penetrant.
I wrote an article a few months ago on SOSAKOnline that detailed care and maintenance of a SAK. The theory is pretty well the same for multitools.
http://www.sosakonline.com/index.php?option=com_content&task=view&id=127&Itemid=35Good luck and make sure to let us know what you think of the RS when you get it!
Def