a rough estimation is between 2-7% of the total content of the page.
But as the above posters said, if they are used in coherent and meaningful sentences, then even higher densities are acceptable...

a related question.
which tag is better for SEs - <b> or <strong>?

if your site's new, then pages showing up and going out of index is quite a normal behavior. Btw, it doesnt have anything to do with the sandbox filter which seems to be about the aging of incoming...

cscg
call it by any name, but a dampening filter does exist which keeps new domains from doing well in G in their early days.

c78
try getting some deep links for the pages which are getting...

from experience, i can say that parameter-carrying urls do get indexed perfectly well, however your page may carry a slighlty more ranking weightage if its url contains your page keyword.

By the...

no need to submit your site manually, just get some links pointed to your site. Google spiders will discover your site automatically.

generally there arent any ranking problems when moving hosts:
you may also want to read matt cutts' blog which provides a nice step-by-step guide in this regards...

case is not a factor considered by search engines in rating websites. Its more of a site usibility issue than a SEO one.

"MSN, however, absolutely loves hyphenated domain names, at this time anyway. That may change."

will have to agree with this statement.
But the hyphenated and non-hyphenated thingy only carries...

whatever happend to the concepts of global accessibility and quick results?
Remember that 80% of world's internet users are still on dialup. They'll be losing out on that demographic.

The first...