many sites are producing apps for iPhone and Andriod. It's WAP and walled garden with fancier technology and more lock to vendor instead of carrier.
These things have WEB browsers... So have many non iTune and non-Andriod marketplace etc gadgets..
Publishers: Code for Web browsers. maybe even with USER menu for screen size. Don't rely on user agents.
A plague on sites with:
No usability at all without Flash (can be bad even on flash enabled stuff or people may not be able to install "latest" flash) or Silverlight.
Any requirement to use Java, except for special applications.
Any requirement to use .Net or Active X at all.
Fixed screen width, if must have, then no worse than 720 wide