Wanted to see if anyone has done some research on standard HTML access key. I have notices after doing some research many sites including Apple have incorporated the accesskey="s" on its search box. I find this extreamly usable if used properly and wanted to get input from the community.
I think the latest guidance is to not bother with them. They often compete with other navigation aids, JAWS for example. I believe people like the BBC in the UK have dropped access keys, and I recently helped build a central government UK site without these access keys.
There's no list of accepted accesskey delegations. WebAIM say that both the UK and Canadian govermnents attempted it and they provide that list on their website. I notice "S" is used as "Skip navigation" there, not "Search" too. Wikipedia use "f" as their search accesskey.
In my state government there is also a standard, but that differs from the UK and Canadian model as well. I think the key is: if you are going to use accesskeys provide information on them for your users (usually a list in your accessibility statement). Hope that helps!