These are the packages that would be merged, in order:

Calculating dependencies ... done!
Dependency resolution took 1.01 s (backtrack: 0/20).

[ebuild  N     ] x11-libs/libXtst-1.2.5::gentoo  USE="-doc" 285 KiB
[ebuild  N     ] x11-misc/imwheel-1.0.0_pre13_p20100827::gentoo  123 KiB

Total: 2 packages (2 new), Size of downloads: 408 KiB