>>By now, this is the widest beta I know of. Yes, this worked like that all that time. Somebody invited you, and you used to get 4 or 6 invitations to give away. Over the time, I should have had about 20 invitations or so, and now I have (last time I checked 50 more).
>>
>>It's like a pyramid scheme, but this time nobody get ripped of money (althoug I do understand the business logic behind it).
>
>I would suspect they want to "officially" keep it a beta for some more time, but make it possible for a large number of people to join.

As far as I know, the only thing that keeps the service in Beta is lack of clearance from the Congress due to some privacy concerns some legistators expressed. These are based on the fact that gmail scans the message you're reading for keywords that allows for the display of context-sensitive ads on the right column (in the same way that Google when searching).

In my humble opinion, this is absolutely dumb. The fact that they ostensible and openly inform you thta they'll scan your message doesn't compromise your privacy any more than when you use Hotmail, Yahoo or any other mail service.

In the meantime, I guess that by now, more than half of the Web users worldwide should be onto this Beta...