In this week's Merryn Talks Money market roundup, there's only one story on our host's mind. Merryn and Money Distilled newsletter author John Stepek talk about US activist investor Boaz Weinstein of Saba Capital and his high-profile attempt to unseat the boards of seven UK-listed investment trusts. Weinstein argues that a combination of weak three-year performance and too much tolerance of wide discounts means investors should welcome Saba's attentions; the boards argue that Saba is self-serving and that victory for the US investor would leave shareholders facing an uncertain future. "Everyone is right", concludes Merryn. But if you're a shareholder in any of these trusts, then what should you be doing about it?