Do a detailed comparison between the Optio W60 and the Olympus 1030SW.

http://www.dpreview.com/reviews/compare_post.asp?method=sidebyside&cameras=pentax_optiow60%2Coly_stylus1030sw&show=all

Honestly, I think at that point, it comes down to brand loyalty.

Personally, I have had more positive experiences with an Olympus over the Pentax cameras - especially in the water proof models.

(I do not own neither camera, nor have I used them.)

If I didn't want a waterproof camera, I'd look at the FujiFilm FinePix F100fd.