One well-known commentor wrote: "The service is great. It is timely. People are engaging with it like crazy. There are rumors that there are already 4.5m people. That might be high. It might be as low as 1m, or even lower, but my guess is that it's more than 1m people already. That already is probably the fastest growing service (0 to 1m) ever. Now it's not completely fair, since when Facebook started, and when Twitter started, etc. those were tiny companies, and Google is huge. However, the product is extremely well executed, and a lot of people are smitten."
How about you? Are you starting to dig around Google+? Chime in on the comments.