New domain - when to take down old site?

[tilly5]

I finally decided to move from my free host (Yahoo Geocities) to a new domain/new hosting service several weeks ago.

Unfortunately, it is impossible to set a 301-redirect on Geocities because I'm not allowed to create a .htaccess file.

So, I have to make do with a meta tag redirect. Right now it is set to 15 seconds and I've got a "We've moved!" message on every single page. I've left the content on the old site intact. On the new site, I changed the layout and added a lot of new content. I've got Google sitemaps on both sites at the moment.

My old site has a good page rank with Google and although I've had Googlebot run over my new site, it isn't showing up yet (I know it is too soon and I'll probably be in the sandbox for months).

What I am wondering is this: when I should take down the old site? Ever? Should I just remove the content (including meta description and keywords) and leave emtpy pages with a Meta-redirect set to 1 second? If so, when should I do this?

I don't want to get penalized for duplicate content.

[EasyCall]

That's a tough one. Other's may have a better idea, but if it were me, I'd leave my old site exactly as it was since it was drawing good traffic. I'd put up all the pages I want to eventually have on the new site with a minimal amount of content - just enough to get indexed without tripping any dup content filters. Then wait - wait until the new site comes out of the sandbox - which might be 9 months or so (reminds me of a pregnacy!) - and then move all the content to the new site, remove all content from the old site and use a meta refresh on each page of old site. Use 0 seconds in the tag.