The short term promise & perils of Nanoparticles

There has been a bit of talk on the promise and perils of Nanobots but I havn't located a thread that talks about a much more near term technology. Here's a couple of links about the current commercialized forms nanotech today.

Biological quantum dots go live
Mighty Small Dots
Nanoparticles Keep Brain Cells Alive
Nanoparticles Used In Solar Energy Conversion
Nanoclay

These are on the market right now(or will soon be) I want to know what you all think are the Pros and Cons about using Nanometerials in everyday products. Example 1: Using Nano-Zinc-Oxide to make Zinc-Oxide cream transparent, silky and absorbant.
Example 2: Stain-Proof, Wrinkle-Proof, Odereater Khakis.

These are the type of Nanotech that you can buy in the store today.