The Accesskey attribute assigns an access key to an element. Elements that support the accesskey attribute include: a, area, button, input, label, and legend, and textarea.
While it seems that Accesskeys is a great idea in principle, implementation brings with it the possibility that it either will not be available to all users, or that the keystroke combination encoded within the web page may conflict with a reserved keystroke combination in an adaptive technology or future user agent.
http://www.wats.ca/articles/accesskeys/19
The UK Government provides accessibility guidelines to which all its websites should comply - including the use of the same access keys:
S - Skip navigation
1 - Home page
2 - What's new
3 - Site map
4 - Search
5 - FAQs
6 - Help
7 - Complaints procedure
8 - Terms and conditions
9 - Feedback form
0 - Access key details