Google+, the rapidly growing successor to the company's failed Buzz experiment, is finally showing signs of integrating with core Google services. On Monday, Google's Mark Striebeck previewed a tweak to Gmail's people widget that will display the most recent Google+ post from a given user. Now that Google is moving towards integrating Plus with services beyond PicasaWeb, here are the five services we'd most like to see Google combine with its social network.

Google Apps

I've said it before, and I'll keep saying it until it's done. Google simply must get on the stick and roll out Profiles and Google+ to its business customers soon. Until that happens, many business users who've already gone through the productivity disruption of migrating their old personal accounts to their Apps accounts won't even bother joining Plus. Perhaps feedback from Ford, which is testing Google+ will speed the process.

Frankly, it's a little shocking that Google continues to encourage Apps users to go start a Plus personal account while waiting for the business accounts to emerge. Just last month, the company booted business pages from Plus. And even if Apps users do go to the trouble of starting Google+ personal accounts for non-business use, they'll have to deal with the hassle of moving their circles to their Apps accounts once the service finally emerges for business. It's an invitation to disaster.

Yes, the business world would like to see Profiles for Apps rolled out right, but we'd also like to see it rolled out soon.

Gmail Inbox

Adding the latest Google+ post to the Gmail people widget just makes sense. What makes even more sense is giving users the option to integrate Plus into their Gmail inboxes the same way Buzz did. There are lots of cues that this would be a counterintuitive move, since Buzz worked this way and flopped. But let's remember that Buzz didn't fail because it worked with Gmail; it failed because it did a crappy job of surfacing relevant posts and left users' private information hanging out for all to see. The one thing Buzz did right was reduce the number of places its users had to go to interact with their social graph.

Google Places

Checking in at visited sites with geo-location has become such an obvious extension of the social media experience that it's a little surprising Google didn't include Google Places integration with Plus at the time of launch. It's hard to imagine that this feature won't be coming very soon, particularly now that Facebook has expanded its geotagging feature to work from any device, even when users aren't actually at the location in question.

If Google wants Places listings to garner serious commitment from the business world, it needs to connect local businesses to its social media users through Places and Plus.

Google Voice

Google Voice gives users a single phone number for all their phones, and lets them text their contacts directly from the browser. If Google integrated Voice into Plus, allowing users to view and send texts and voicemail transcripts from Google+, it would expand the relevance of Plus as a central inbox. It would be even cooler if Google+ and Voice converged within the Gmail interface, creating a one-stop social inbox for everything.

Google Sites

While Google Sites isn't huge with consumers, it's massively important to enterprises that use Google Apps. As a tool for building and managing intranets, the possibility of connecting Sites to Google+ social streams opens up meaningful opportunities for businesses to foster more dynamic communication among workers at all levels of an organization. I'd expect Sites integration to come along with Apps integration, but let's hope it doesn't get left on the cutting room floor.

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