why should it wear out? AFAIK, everything related to eMMC is protected by hardware wear-leveling. Only 256 MB NAND doesn't have hardware leveling - but, it does have it in software, except kernel part (that's why uboot is theoretically better than multiboot)

So, it doesn't seem that using SWAP partition wear eMMC more than just writing files.

Also, remember that using swap on microSD boost performance (at least in Maemo), due to avoiding I/O race between swap and regular files, located on same eMMC. I don't see any reasons, why should it behave differently using Kubuntu (seems hardware'ish), so ideal settings would be to use swap on microSD, not eMMC.

/Estel