How can ebay make 3.3 millions pages indexed???

[onthink]

http://pages.ebay.com/sitemap.html?s...me=h:h:smap:US

This is ebay's sitemap and ebay have 2.3M pages indexed by google.
Almost all ebay pages have keywords/titles in google SERPs instead of just simply links there in SERPs.

I think, maybe it is reason of time being to make so much pages indexed. It is not the reason of sitemap.
Presumably, if google indexed 500 ebay pages everyday, three years will make 0.5m pages indexed,since ebay's content changes every minute.


I don't know, I am muscle in on making my all 10000 pages indexed fully with pages name in google. Hard work.....