About browser applications: Native code vs Applets with certificates

I've been reading about the new native client support for chrome and I was wondering what are the advantages/disavantages compared to writing Java applet with a certificate?

Quick note: A java applet with a security certificate can e开发者_运维问答xecute code on the user machine and "by-pass" the Java Security Manager.

Thanks,

-hbt

Native client can be compared to Java applet without a certificate. The difference is speed (native client is faster) and portability (you need several versions of your code (x86, x64, arm)). The rest is difference between java applet with and without a certificate.

Questions to ask:

1. What browsers are you targetting? Only chrome?
2. What devices are you targeting? Desktops or also iPhone, RIM etc. On iPhone you CANNOT run applets.
3. Will the end users have a flexibility to install Java Plugin for the browser?