I've done it twice. While I see the merit in sealing the wood, I chose not to. Both cabinets turned out fantastic and show no signs of artwork lifting.
Here's how I did it:
Remove old art. How you do this varies with the 'luck of the draw'. I've done a couple side art replacements, and with one cabinet the original art just peeled right off. The other one I used a heat gun to help pull it off.
Sand any remaining adhesive residue. 220 grit on an orbital sander worked for me.
Chip away any loose wood, then use tape around any edges that are damaged and apply Bondo. Sand to the correct shape.
I then sanded the cabinets one last time with 220 grit on an orbital sander. Use tack cloths to get every bit of dust of the side of the cabinet you're working on so it won't get stuck between the cabinet and artwork.
I then layed out paint cans to hold the art down and spent quite a while measureing to get the art lined up.
To stick the art down I removed the paint cans from the bottom half of the art. Then I carefully removed about 2 feet of backing from the art, and stuck it down using a plastic bondo spreader (a credit card will also work).
Now that the bottom is stuck down and lined up, take off all the paint cans and roll up the art to the bottom. Now slowly unroll (a helper is needed) a couple feet of art at a time, and carefully stick it down as you go.
I found it helpfull to cut off sections of the backing material as I went so you don't have to unroll the art and roll up the backing at the same time.
I then removed the protective top sheet and made sure the art was firmly stuck down all over, and there were no air bubbles. Small bubbles may be removed by poking the center of the bubble with a pin. I let the art sit for a few hours just in case it needed to expand/contract a bit after being applied, probably not necessary but it also allowed me to relax after the stress of applying the art.
Trim the art with a sharp new blade of your choosing, apply T-molding and admire your work!