Yesterday the New York Dow Jones index of big American companies rose 3.3% taking it to 9625, roughly 25% higher than the intra-day low seen on October 10.
The London FTSE 100 rose 4.42% to 4639, a 20% increase on its low point of just a couple of weeks ago when it fell below 4000.
This morning (Wednesday) it slipped back in early trading as reality (and probably profit-taking) made a reappearance.
France and Germany both rose strongly yesterday, despite BMW saying that it might seek state aid for its finance operation, and this morning Japan, Hong Kong and Singapore all rose by over 4% each.
So has Obama waved his magic wand already and restored confidence to the markets?
Because confidence is the key.
The billions, if not trillions, of mortgage-backed securities that banks hold worldwide aren't worthless because they're not paying interest (most of them still are) but because no-one will buy them.
Banks won't lend to each other, or will only lend reluctantly, because they're fearful they might choose the next Lehman Brothers, but that's hardly likely with governments underwriting the big banks' deals.
But Obama offers a fresh start in the United States and, to an extent, that will restore confidence as the markets have lost faith in Republican policies and are willing to try nearly anything, even Democrat policies, usually decried as tax and spend.
His first, crucial decision will be his choice of treasury secretary.
The Republicans' Hank Paulson, former boss of Goldman Sachs, has striven manfully to bring the credit crunch/ financial crisis (choose your poison) to an end by making available $700bn for bank bail-outs and, in effect, breaking the model of freebooting investment banks (in one of which he made his fortune of course).
Obama needs to choose a treasury secretary who can help to fix Main Street as well as Wall Street, without going back to the days of "Clintonomics", easy credit for everyone, which many blame for causing all this trouble in the first place.
He'll be praying there are no more banking-induced disasters before he takes over officially in January.
Rate cut set to spark banking row
HSBC chief operating officer David Hodgkinson let the cat out of the bag the other day when he told ITN that passing on Bank of England interest rate cuts to customers was only an "aspiration."
This is the first big test for new business secretary Lord Mandelson who has already stated that that he expects any such cuts to be passed on, although he hasn't so far said "in full."
HSBC, of course, can do what it likes as it hasn't had to go cap in hand to the Government for extra cash so its decision to support borrowers or not is its own affair.
Earlier this year it was the first bank to go into the market with a fixed price offer on remortgages so it may not want to attract many more UK customers.
But the other banks, with the exception of Barclays, which has raised the extra capital it needs from the Middle East, will find it more difficult to resist Lord Mandelson's wishes.
Royal Bank of Scotland's new CEO Stephen Hester has said that it will boost its lending to personal customers and small businesses.
Not that he has a lot of choice as the Government has acquired £5bn of preference shares in his bank and is underwriting £15bn more.
The banks will be hoping for a cut bigger than the expected half point on Thursday (rates are currently 4.5%) because that will give them the opportunity to keep some back for themselves while still reducing mortgages.
Building society Nationwide is putting its money on a three-quarter point cut, which sounds very Bank of England-ish, not a panic-driven full point but more than many expect.
Which would certainly give the banks some wriggle room.
Industry takes a less sanguine view, with Jaguar and Land Rover CEO David Smith saying a full point cut is essential.
New Indian owners Tata Group, who bought the two car marques from Ford for what looked to be a bargain basement £1bn, must wonder what's hit them as absolutely no-one is prepared to buy a luxury car at the moment, not even Jaguar's snazzy new saloon.
Lord Mandelson has taken a bit of stick since he returned to the Government, what with gossiping to George Osborne in Corfu and hanging out with cash-strapped Russian aluminium "oligarchs."
But as a politician Mandelson has an unerring ability to sniff out weakness in others (while mostly oblivious to his own).
He knows that there's real anger out there with the banks, from big companies as well as small businesses and individual borrowers.
The banks will be taking a big chance if they fail to pass on all, or nearly all, of this week's rate cut.
M&S takes knife to marketing budget
Marks & Spencer is to trim its chunky £140m marketing spend by 20% following disappointing half-yearly results that saw profits drop by a third and like for like sales by 5.7%.
Turnover edged ahead to £4.2bn, driven by expanding its international business.
The news will disappoint marketers as advertising has been the main sales driver at M&S, and big money TV advertising with Twiggy and her mates at that.
But a decade ago M&S didn't advertise at all so it's hardly a statement that it doesn't believe in advertising now.
Executive chairman Stuart Rose won't be too disappointed though.
He's been saying for a year now that a storm was brewing in the wider economy and he's been proved spectacularly right.
With other retailers like Arcadia and Next also reporting sharp slowdowns M&S's performance doesn't look as bad as it did a few months ago when Rose made his first profits warning.
The shares have fallen steeply from the heady days when Arcadia's Sir Philip Green tried to buy the company.
It could be time to make a small investment.
Stephen Foster is a former news editor of Campaign, former editor of Marketing Week and Evening Standard ad columnist. He is a partner in Editorial Partnership and writes the blog www.editco.net and Politics of the Media for Brand Republic.