For those of us who like to autogen content. Hear are some secrets google appears to be hiding in plain site. My theory is that if it appears in their results then its safe to say it is what they put in their database.

(FYI... my sites tend to have millions of pages and usually index around: Results 1 - 100 of about 259,000 so these patterns mean a lot to me)

I'll Start With The Conclusion:

There is no hard fast rule, but these appear to be the content details that Google favors when a keyword is "over saturated" like "games" or "cars"

• Title should be no longer than 68 characters with maximum of 5 keyword repeats
• Summary Text should be no longer than 155 characters with a maximum of 8 keyword repeats
• URL should be 14-75 characters with a maximum of 2 keyword repeats
• Your cached pages should be no older than 2 - 7 Days ... less is better
• Number of Similar pages doesn't appear to matter
• Your domain name should be about 14 characters including the top level domain
• You document size ,no images or includes, should be about 48K and probably shouldn't exceed 100K if possible
• More results doesn't appear to effect placement. But 539-2,300,000 pages was the Top 100 range of pages for that feature

Some Interesting Limits From the Top 100 Google Results For Searches Like Cars & Games

Title Sizes 4-68 characters

* LOW - cars
* HIGH - Enterprise Rent-A-Car: Rental Cars at Low Rates and Weekend Specials

Note: _... at the end is subtracted because it adds no value

Summary Text 0-155 characters

* LOW -
* HIGH - Research Luxury cars at Automotive.com; get free new Luxury car prices, invoice pricing, MSRP, dealer cost, and more, buy a new Luxury car, or read reviews

Note: _... at the end is subtracted because it adds no value

Keyword Repetition in Summary 0-8 Times

* LOW -
* HIGH - Mara pets games has free games and free flash games, such as arcade games, action games, puzzle games, sports games, online games and more.

Note: Technicality 9 if you count game and games as same - Free game downloads & online games at Big Fish Games - A new game every day! PC games & mac games - Play puzzle games, arcade games, mahjong games, ...

Keyword Repetition in Title 0-5 Times

* LOW -
* HIGH - Games - Play Free Games, Online Games, Flash Games and Arcade Games

Keyword Repetition in URL 0-2 Times

* LOW -
* HIGH - fbi.gov/kids/games/gam*es.

Document Size 1-224 KB 48KB Average In the Top Ten and < 5 in top 100 are 100+KB

* LOW - aplu***smath.com/Games/ - 1k
* HIGH - amazo**n.com/THQ-Cars/dp/B000GUQJQ8 - 224k

Number of Similar Pages 0-30 8 out of top ten were 27 or higher

* LOW - google.co**m/search?hl=en&safe=off&client=safari&rls=en-us&q=related:dmoz.o***rg/Games/
* HIGH - google***.com/s***earch?hl=en&safe=off&client=safari&rls=en-us&q=related:games.aol.com/

Cache Date Not Cached or Feb 22-27 ...Top Ten Feb 26-27 Bottom Ten Feb 22-24

* LOW - 209.85.173.104/search?q=cache:FIu18_ego_AJ:ww.no***rthpole.com/Clubhouse/Games/+games&hl=en&ct=clnk&cd=100&gl=us&client=safa**ri
* HIGH - 209.85.173.104/search?q=cache:5t-TD5wyBAQJo***pcap.com/+games&hl=en&ct=clnk&cd=13&gl=us&client=safari

Note: Generated this data on Feb 29

Number of "More results" when present 539-2,300,000 pages
* LOW - More results from apple.com » Results 1 - 100 of about 539 from ap***ple.com for cars.
* HIGH - More results from ca**rs.com » Results 1 - 100 of about 2,330,000 from cars.com for cars.

Size of URL 14-75 characters

* LOW - gam***es.com/
* HIGH - amaz***on.com/kids-games-board-classic-dvd-travel/b?ie=UTF8&node=166220011

Size of Full Domain Name (word.word) 6-23 characters Avg 14

* LOW - bu.edu
* HIGH - cartoondollemporium.com

Size of Primary Domain Word (word).com 2-19 characters Avg 10

* LOW - bu.edu
* HIGH - cartoondollemporium.com