The happy couple back in May. (David Livingston/Getty Images)

After lots of speculation about whether they would or would not solidify plans to tie the knot — as of yesterday, In Touch Weekly was insisting that Spears had turned down Trawick’s proposal earlier this month — it appears the two are moving forward toward marriage.

Us Weekly reports that a Spears source has confirmed that the couple, who have been together romantically since 2009, got engaged over dinner last night. They are expected to celebrate the union at a bash tonight at Las Vegas’s Planet Hollywood. Spears also tweeted a message that seems to support that story.

“OMG.,” she wrote. “Last night Jason surprised me with the one gift I’ve been waiting for. Can’t wait to show you! SO SO SO excited!!! Xxo.”

Presumably we can look forward to additional tweets from the pop star, featuring photos of her ring and a lot more exclamation points.

Of course, there are a couple of hurdles the pair still has to cross before a wedding day takes place.

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As the New York Post notes, Spears, 30, will have to get approval to wed from a judge because her legal and financial affairs are still handled by her father. That arrangement was the result of a conservatorship created in 2008 after Spears’s head-shaving, losing-custody-of-her-kids meltdown period. Trawick, 40, also reportedly will sign a prenuptial agreement.

Assuming this all happens according to plan, this will be Spears’s third marriage. The mother of two was married to Kevin Federline for almost three years, and then for five minutes — all right, fine, two days — to her childhood friend, Jason Alexander, the non-George Costanza version. That marriage was annulled. We feel confident that her marriage to Trawick will last longer.

View Photo Gallery: See more photos of Britney through the years.