Update: It's live.

Last night, we revealed a project codenamed Bigtop that Google has been working on for a few years. And now, I feel confident enough to announce that it's launching later today as 'Inbox by Google' (not to be confused with Inbox).

According to multiple sources, the service, which has been in development since 2012, is going to be invite-only at launch, just like Gmail was, and will at first target Gmail users. Predictably, it will be available at inbox.google.com.

Of course, if we manage to score any invites and can spread more of them around, I'm going to probably spend the remainder of the day doing so on the site and Google+.

[leak_disclaimer]

Another curious thing to add to the rumor pile: Calendar is expected to receive a major overhaul as well, and it's codenamed Timely. I don't think it's related to the purchase of Bitspin, the developer of an unrelated app called Timely, which happened in the beginning of this year, but anything is possible. It'd be pretty amusing if the Timely team actually joined the Timely project once at Google. It's unclear if project Timely will be announced with Bigtop / Inbox by Google or will be revealed separately later.

There's not much else to share at this time - all we have to do is wait a little longer.

In the meantime, I'm getting giddy with excitement. What about you?