Imagine you are visiting a Website that offers free access, but only to registered users. At the top of the page are a number of options. You can create a new identity, or you can just sign in using your Facebook account, your Google account, or one of several other online identities you already have.

Which do you pick? And could your choice tip the balance of power between the big internet companies?

While Yahoo’s management has come under relentless criticism this year for its decisions and performance, there was a reminder today that it was making even more questionable judgement calls back in the last century.

Yahoo announced it had reached agreement with CBS Radio to take over the running of its 150 Launchcast internet radio stations from early next year.

Today they should all be playing funeral dirges for Yahoo’s 1999 acquisition of Broadcast.com for $5.7bn. Admittedly, this was an all-share transaction at a time of inflated valuations, but co-founder Mark Cuban was quick to cash in and invest elsewhere, making himself a billionaire in the process.

President-elect Barack Obama may have earned praise for his innovative weekly addresses on YouTube, but another well known Democrat stands accused of overdoing it.

Gavin Newsom, the mayor of San Francisco, is releasing his annual State of the City speech on YouTube this week, all seven-and-a-half hours of it.

“Just what I wanted, somebody imitating Al Gore for seven-and-a-half hours. The guy did a Fidel Castro,” Aaron Peskin, president of the city’s Board of Supervisors, told the San Francisco Chronicle.

Mayor Newsom’s address, filmed strictly for the internet at the California Academy of Sciences, has been made slightly more digestible by dividing it up into 10 “webisodes”, 30 to 45 minutes in length, released over the course of the week. But it still represents more than a mouthful for YouTube viewers used to clips with an average length of 2.7 minutes (the most watched webisode is his 1 minute 23 seconds introduction.)

Mayor Newsom, a policy wonk, says he has a lot to share that goes beyond the usual hour-long speech to a bored Board of Supervisors, and a YouTube channel is the best way to deliver it.

He had complained about the “YouTubeification” of politics at last month’s Web 2.0 Summit in San Francisco, in particular, about the online clip of him singing “I Left My Heart in San Francisco.”

His move to embrace YouTube to get his message across, unfiltered by the media or reduced to a soundbite by a YouTube uploader, is something of a California bearhug – suffocating and likely to make people run a mile to avoid.