I submitted my first Google Sitemap on July 1, 2006. Since then I have
submitted about 5 updates to it, but when I goto my Webmaster Tools
screen and view the 'Sitemaps' tab, it still says it was SUBMITTED on
July 1, 2006 and LAST DOWNLOADED 22 hours ago.

What's the deal? Why won't this give accurate info?

What's incorrect about it? You said yourself you last submitted it on
July1 2006 - so that's what it says.

Once a sitemap (thus a site) is submitted, the robots download the
sitemap  and crawl the site regulalry.

I have had a similar problem and have yet to get an answer that I
understand or can comprehend.  I've read the other posting message to
this question and wonder how often the crawling and indexing occurs and
when can I expect my new sitemap & information to appear in the
Webmaster Tools Data information?
Thanks, any help is appreciated.

As Webado has advised, once you have submitted your sitemap, googlebot
will regularly download the sitemap to see if there has been an update
to it. Hence the Sitemaps page gives two dates. The first is the date
you submitted your original sitemap, and the second date (or time) is
when your sitemap was last downloaded and read by googlebot.

To confirm that your site is being accessed - you can check in
Webmaster tools: click the diagnostic tab, and choose summary on the
left hand side. At the top of the summary info page, under title
indexing - it will tell you the last time googlebot accessed your site:

eg: "Googlebot last successfully accessed your home page on Jan 9,
2007. "

Please advise if you need more help...

Thanks for the answers. It just seems to be a non-informative way of
letting us know that things are indeed taking place with our sitemaps.
Realistically, how important is it for me to always be reminded that my
sitemap was submitted on July 1, 2006? I know it was submitted. It even
shows a status of OK. It seems to me that they could be using that
space for more pro-active data rather than a superfluous submission
date which is why I was confused about it. But since you confirmed that
all is well, then I won't stress over it. Thanks. :-)