Google and Twitter couldn’t make a deal to renew their real-time search partnership, and now Google+ is plowing ahead on its own. A new Google+ feature makes searches on the network more timely, social and shareable. Google+ users can now post updates to their streams directly from search results.

If you search for a topic or hashtag, such as “SOPA,” a post box at the top promps the user to “join the discussion.” Posts from this box include the note “Shared from the Google+ SOPA stream.” The topic name links back to the search results page.

Earlier this month, Google unveiled its pivotal effort to make search more social. Its “Search, plus Your World” update changes its search engine from an unbiased look at indexed pages to something influenced by your friends and contacts. Google’s bet is that this helps users find more relevant results.

Google’s real-time, topic-tagged social searches now give it a graph of the online public’s interests, which is the same valuable commodity on which Twitter is trying to build its business. Twitter’s torrent of real-time data produces trends, and it sells promoted ad spots on those trends. For users, search is an essential part of exploring their interests on these networks, so it’s a crucial spot for these networks to monetize, too.

Twitter has been slow to build its own search product. For a while, Twitter just fed its results to Google. But that put too much power in Google’s hands, and now Twitter won’t play ball. Twitter acquired its own social search startup last September, but nothing has come of it yet.

Much like Twitter’s website, Google+ search pages show trending topics along the right side, employing its real-time search and hashtags to discover new, timely content. Today’s update makes Google+ searches more visible by including them in sharing. Google+ also added its “What’s Hot” section to the mobile Web version today, adding another way to discover real-time Google+ stories.

Do you use search or browse for topics on social networks to find stuff that interests you? Or do you discover content in other ways? Tell us in the comments.