There have been a few posts about filling up the cracks between vinyl coated drywall. Most of the people here tend to go the tape and drywall compound route. Spackle cracks due to the shifts in the wallboard, but I don't know how a flexible caulk would do.
I would also like to know the answer because we are moving into a home next month that I want to cover the gaps. I will go the tape and compound route if I have to, but if there is a less time consuming method...

I just found a link to a product called "Faster Plaster" by Flexiwall. It is supposed to cover over the gaps between the wall panels (when the strips are gone) and be paintable or even re-wallpaper-able.
I have had excellent results in just taking down the strips and papering over the whole wall, gaps and all. A heavy wall covering and gaps of 1/2 in or less is best. Paintable wall covering is great if you want the texture, I love the stuff.
Also one might consider covering the walls with fabric....this can even be done in a removable manner so that it can be changed with little trouble. Links: http://www.rentaldecorating.com/quick_fix_fabric_on_walls.htm
http://home.howstuffworks.com/how-to-install-wall-treatments2.htm
I'd just worry about the starch drawing bugs...personally I'd chose a non-organic adhesive and just paint over the fabric when it came time for a change.

My husband purchased on line a product called Krack Kote. This is the web site to check it out: http://www.tkocoatings.com/krack-kote.html, and he would use nothing else now that he has used this product. We have had to help out a few folks that also have MFHs and my husband used this in their houses and they are very satisfied with no more cracks coming back. I am sure there are other products but we have had good experience with this product which was recommended to us by a MFH manufacturer.

I did this with great success, the trick is to find a great flexible caulk that won't shrink.
I've used DAP Dynaflex 3.0 it's a gold tube with blue lettering.
Invest in a caulk gun that costs around $10-15, it is worth it!
For the cleanest lines, mask each side of the gap with masking tape, use as little caulk as possible (seriously only cut the tip a teeny bit) and use a popsicle stick (or craft stick) to push the caulk into the gap and leave a really clean seam. Just use the stick the same way you used the caulk gun, from top to bottom, and wipe of excess.