Today no 1 , tomorrow no 60

[Heat]

I am doing work for 2 websites in the same industry, keywords quite the same: www.blinds-wise.com and www.flamingoblinds.co.uk. In May, I have started a linking campain, for the no1 keyword, "blinds uk", flamingoblinds.co.uk was ranked in the 4th positions and blinds-wise.com in the 190th. There are links from flamingoblinds.co.uk to blinds-wise.com, but not the other way round. I also have, from our other websites, hosted on the same server/IP, links to blinds-wise.com like from: eshop-wise.com or webdesign-wise.com and so on.For about 6-8 weeks flamingoblinds is in 2nd position (sometimes in 1st position) for "blinds uk" keyword.
The problem is that blinds-wise.com is staying 2 days in 1st position for "blinds UK" and after that goes somewhere in 20-70 position, but it comes back after 2-3 days.This is happening for about 3-4 weeks. What's wrong with blinds-wise.com? Could you suggest me what could cause this problem? Is it from the backlinks from the same IP address? Am I beeing penalised for this or for something else? Any idea is much appreciated. Thank you in advance.

Best regards.

[Jamie]

I don't think it is you my site as been doing the same for the same period and I am not doing any changes. But I will only stay in the top position for an hour or two and than drop 60 to 100 back for most of the next 24-48 hours and than back to number one or two for an hour or two. This is happening with almost all of my keywords.

[Artyom]

Hi,
the same situation with the site I'm doing SEO for -
http://www.adulttradeshowdesign.com and right now this is like couple minutes ago I was on #1 place on my main keyword 'adult trade show design' and now it's nowhere and then get back on top again. I assume this is somekind of Yahoo Dance or something;-)

I'm gonna keep checking it throughout the day to see if it's permanent situaation.