My best guess, based on site: oddities, supplementals rising to the top of a site: command, and watching a new 301 get noticed, and then unnoticed by Google during this time, I think it's either an old data push, or a bad data push. My gut says old data, but bad data could fit. And if this data is a limited set, then it would only affect some sites. Again, just a guess, but one based on observations.

I've watched new content fly into the index, but the linkage doesn't seem to pass value as quickly as it feels like it should. It's like the horse and cart are moving at different speeds.

If this is the new normal, I figure there will be screaming and hollaring for a few more weeks until people learn to live with it.

My traffic looks about normal, allowing for the usual holiday dip.

My data certainly indicates that Goolge introduced old data back into the mix. On about 1/6 of the datacenters I've been monitoring I'm seeing old inbound link data. I have been seeing new pages get indexed.

Quite frankly GreyWolf (or was it Donna) who suggested a bad data push = old data re-introduced into the SERPs. I've seen some spammy (off topic web sites) and older web sites in my field pop back up to the top, whereas I've lost 90% of Google traffic for some sites.

I have seen a few newer sites pop back into the index that previously had disappeared. They basically just took up residence in the top 10 with other authority websites that were new to the query. Lots more blended and useful results. Looks like some tweaking for relevancy purposes, or adjusting so the listings don't favor as many big authority sites. It could be a good thing. I could do with less Wikipedia listings in my searching.

I actually saw a huge jump in our positioning and 90% of our top competitors drop off the listings completely.

My wifes site however (http://www.stellarlifestyle.com.au) dropped considerably (nowhere to be found)which has given us the opportunity to completely re-design and develop the site with new SEO as the focus.

My general feeling is that there was some minor tweaking of the system and that our competitors who i guess had become complacent and confident in their ranking got bumped. I know that we have been very aggressive in our approach to SEO just to be able to compete with the big guns who have now completely disappeared!

I think it's related to DMOZ's server issues:

Their public forum contains this announcement:

"We are currently experiencing technical problems with our servers. Currently the public pages are static pages that have been generated from a backup. This means:

(1) the public pages do not reflect the most recent updates made to the directory;

(2) scripted pages, including site suggestion and application forms, are not functioning; and

(3) editors are unable to check the status of new editor applications.

UPDATE: December 18, 2006 -- Editors have regained access to the editors server and the public pages are now up-to-date. However, the public ODP scripts (including site suggestion, update listing, editor application, and abuse reporting) are still not available and we currently have no ETA for their return. Please be patient and, again, we ask that you not start threads asking when those forms will be available again--we will update this announcement when we have further information. Thanks."

http://www.resource-zone.com/forum/showthread.php?t=45325