From the source link that was posted earlier, it should be deployed during this month (May). So most likely they will work their way gradually to all Yahoo Mail users by this month's end.

Yeah. You will notice in quantcast (a site rater) that Yahoo has around 65m views per day. It's the number one site (2- google), and now they are expanding their mail to unlimited storage. God, talk about killing competition. o_O

Very unprofessional, if you ask me Sure, this "trick" might do well with Internet rookies (those that don't really know how it all works), but some more advance users will immediately realise this is overselling. Not having unlimited storage for is not what will lure them away from using Yahoo, but the fact that they are resorting to lies. I'm in no doubt that Yahoo! will be able to support all that mail, as only a handful of people will user over a few hundred megabytes worth of e-mail.

Google has had a storage limit ever since (though it is increasing constantly - neat move), and they've never had competition, as I can see it. What's more, I find it hard to believe that a GMail user will switch to Yahoo just because of this. As miCRoSCoPiC^eaRthLinG already mentioned, GMail is fast, secure, lightweight and easy to use, in contrast to Yahoo, which is... Bulky. We can just hope that new users will be directed to GMail as well

Just to toss a quick point in here that's likely been mentioned already...

As I mentioned in another thread, I use Thunderbird to view all my email...
And anyone else who does do this... Server Email Storage is pretty much completely useless.

Email clients that download the messages off the server and onto your computer, it instantly no longer matters how much email storage you have on the actual server since all emails are now being stored directly on the computer.

And, even on a totally other note:

Before I started deleting emails off the Gmail server and just purely downloading them to Thunderbird, I never deleted anything at all.
For about a year and a half my exponentially increasing email count was being added onto the Gmail server, it went well past about 3,000, I think...
Anyway... I tihnk I was at about 4% of my total storage space..

So, where is the real need for unlimited?
The only way to even really fill up Gmail is if you send alot of programs/powerpoint documents/movies/music/lots of picuters/etc. But instead of keeping all those files on the server long enough to actually fill up the inbox, you might as well find somewhere else to upload them, or just download them to your computer and then remove them from the server.

Anyway, just wanted to add in my argument.
I think that even Gmail's 2gig storage is a little bit unneede for emails.
I was fine with Hotmail's old, really small amount of storage, the only reason I even even converted to gmail is cause it woludn't let me configure Hotmail to work with Thunderbird or Outlook like I wanted to make it do.

I think that we're taking a bit wrong approach. We all judge yahoo's move as a plain marketing trick.

Pause for a moment and take a look at it from a different angle, the angle of google.com. For years the company has been enhancing its otherwise basic service (internet searching) with multiple other (useful) features - translations, maps, office software, and now the brilliant e-mail service. Up and till now the approach worked flawlessly, with company's value and number of users rising even higher, which seemed impossible after achieving the status of (one of) the best search engines ever. And yet they are about to introduce new features (automatic translation of search queries, default searching in book, movies and pictures databases + revamped interface), constantly adapting, being the topic of media news all the time.

Now, let's get back to yahoo. It's one of the biggest e-mail providers, they have a news portal, and...? I don't know about you, but for me yahoo got a bit dusty over the years, and we all know that who doesn't move forward, stays behind. Now, with google growing in power, and yahoo not looking forward to loose its market share they've adopted a new strategy. The only strategy that enables them to fight with google - the exactly same strategy of development.

Let's hope unlimited e-mail is just a prelude to unlimited file storage, and even then it's a first step on a longer road. Don't get me wrong, I don't favour yahoo, especially that I hate big, bloated, and slow software, but who knows what may happen if google kills his competition and none remains...

And a bulky interface

Nevertheless, I agree with you completely - Yahoo slowed down its pace, which Google (ab)used that. Now they want to get back in the greatest-service-on-the-Internet race, but they will not make it just by following suit. They need to think of something new and useful, or at least improve an existing service that people aren't really keen on. That's what's Google has been doing all this time, and we are fully aware where that got them

Well I must say, this is a bold approach by yahoo....however I am guessing that they will have some issues associated with this, or some things in their terms of service about sharing the space with other users, and if a user is compromising the space in any way (using too much of it) they can terminate the mail account or something (kind of like what happens with hosting that offers unlimited space or bandwidth, etc....

I agree with mvs.en. I've seen one of my classmate's e-mail in yahoo and he has 3000 messages. He didn't even fill up most of the percentage. Filling up even 50% of your e-mail storage would be wasteful, when you know most of it is spam. The unlimited e-mail storage isn't really much of an upgrade, but I have to say, this would draw new users to the internet because unlimited is such a big word.

I never really liked Yahoo mail, having unlimited emails doesn't really change anything.

But then again I wouldn't need that many, heck I don't even need as much as Gmail offers and I think thats what a lot of these silly things rely on.

It's just meant as hype.

Unlimited storage.. I don't really see the point, I have a Gmail account, and I've had it ever since it came out and I'm not even over a gig, and I get around 10 to 15 emails a day.