Gmail Contacts size increased to 25000

There was a previous HN discussion about this limit at <a href="http://news.ycombinator.com/item?id=2263093" rel="nofollow">http://news.ycombinator.com/item?id=2263093</a>. It included some speculation about why Google would limit the number of contacts.

I'm pretty sure that number exceeds the human capacity to maintain discrete external identities for individuals we know, have met, or know of.<p>Interestingly, it's about 100x the upper limit for Dunbar's number: <a href="http://en.wikipedia.org/wiki/Dunbars_number" rel="nofollow">http://en.wikipedia.org/wiki/Dunbars_number</a>

Can anyone elucidate the trade offs in not having a limit at all and ultimately simply limiting the max number of contacts by the storage that they've already issued to users? Are contacts viewed as separate storage from email?<p>(25K contacts at 128 kb yields 3 gigs of storage)