This week's Kalshi lineup got shaken up, not stirred: a stunned Grand Slam draw, a senator's surprise convention cameo, new 007 rumors, and a fresh wave of AI hype. Here's what moved each market and why the next few days could move it again.
US Open Men's Singles Winner
Carlos Alcaraz's title defense ended at 3:33 a.m. on Wednesday, the latest finish in US Open history, when Ben Shelton beat him in five sets to snap an 18-match Grand Slam winning streak.
The loss reshuffled the outright winner market: top seed Alexander Zverev is now the clear favorite, with Shelton right behind him after the biggest win of his career.
Why It's Worth Watching This Week
Neither man is through yet. Zverev faces unseeded Karen Khachanov on Friday, while Shelton meets fellow American Frances Tiafoe in a rare all-US semifinal. Whoever survives goes straight into Sunday's final, so the market should see another sharp move before the weekend.
Our Take: We lean toward Zverev, as he's reached two straight major finals this season. He's also playing his best tennis of the tournament, and his semifinal draw looks lighter than Shelton's on paper.
Sabalenka vs. Pegula (US Open Semifinal)
Aryna Sabalenka and Jessica Pegula meet tonight, with the former chasing a third straight US Open title. Sabalenka holds a wide lead in their head-to-head, but Pegula beat her in three sets at Berlin earlier this year: the one recent result working against the favorite.
Why It's Worth Watching This Week
This one resolves tonight, so the price will move fast once play starts. Sabalenka has reached six consecutive US Open semifinals and carries a strong hard-court record, which is why she opened well ahead of Pegula here.
Our Take: We're siding with Sabalenka, mostly on her hard-court results and her habit of grinding out three-setters at majors this season. Pegula's Berlin win is real, though, and worth watching if this one goes long.
Next James Bond Actor
The next-007 market jumped after Gary Oldman, Jack Lowden's co-star on Slow Horses, told a Canadian talk show that producers have "made their choice" and that his fingers are crossed for Lowden.
Amazon MGM hasn't confirmed anything, but the comment pushed Lowden from a middle-of-the-pack name into the clear leader.
Why It's Worth Watching This Week
There's still no studio confirmation, and producer Amy Pascal has described the casting process as slow and methodical, with an announcement possibly coming by year's end. That gap between rumor and confirmation is exactly why this contract keeps reacting to outside comments: any actor or insider who talks can move the price again before Amazon says a word.
Our Take: Lowden looks like the name to beat right now, since Oldman's comment reads like more than a friendly guess. Paul Mescal and Jacob Elordi have both turned up on earlier shortlists alongside him, though, so either name is worth watching if a new report lands.
Who Will Switch or Leave Their Party This Year?
This contract asks which member of Congress formally switches parties or cuts ties with their own before year's end, and it just got a fresh push.
John Fetterman made a surprise video appearance at the Republican convention this week, praising President Donald Trump and fellow Pennsylvania senator Dave McCormick, even as he keeps insisting he has no plans to leave the Democratic Party.
Marjorie Taylor Greene remains out front after publicly declaring in June that she's "done" with the GOP, without registering anywhere else.
Why It's Worth Watching This Week
Both leaders sent mixed signals within days of each other, and with the midterms less than two months away, expect more headline-driven swings like this one before November.
When Will the Riemann Hypothesis Be Solved?
This contract isn't really about anyone solving math's most famous open problem: it's a set of timelines (before 2028, 2030, 2032, and 2035) on when that might happen.
The near-term line moved sharply this week after an unconfirmed rumor spread that Anthropic's Claude had made headway on the separate Navier-Stokes problem, which pushed AI-math hype through related contracts like this one.
Why It's Worth Watching This Week
The real news underneath is narrower than the rumor suggests: an unreleased Claude research model did raise a technical bound tied to the Riemann zeta function back in August, and Anthropic itself says that result doesn't point toward an actual proof.
Because this contract reacts to sentiment as much as substance, any new lab announcement, confirmed or not, can move it fast, which is exactly what happened this week.
