I’m sorry to hear that because I’m a very sincere user of Gmail for many many years and so it is the only mailbox for me currently.This failure means that I lose my contact temporarily on the method called “Email”.It’d been some kind of disaster for me,really it is.

In a Google Discussion forum,a post sounds like an official announcement is just showing:
We’re aware of a problem with Gmail affecting a small subset of users. The affected users are unable to access Gmail. We will provide an update by February 24, 2009 6:30 AM PST detailing when we expect to resolve the problem. Please note that this resolution time is an estimate and may change.
Well,I could only wait in front of the computer and keep trying on it.Perhaps I should have some alternative mailbox,right?
UPDATE 1:
I found the latest announcement from the official Google Blog there:
If you’ve tried to access your Gmail account today, you are probably aware by now that we’re having some problems. Shortly after 10 9:30am GMT our monitoring systems alerted us that Gmail consumer and businesses accounts worldwide could not get access to their email.
We’re working very hard to solve the problem and we’re really sorry for the inconvenience. Those users in the US and UK who have enabled Gmail offline through Gmail Labs should be able to access their inbox, although they won’t be able to send or receive emails.
We’re posting updates to the Gmail Help Centre at http://mail.google.com/support/ and Google Apps users can visit the Google Apps help centre at www.google.com/support/a.
Thanks for bearing with us while we sort this out. We’ll report back as we make progress.
Posted by Acacio Cruz, Gmail Site Reliability Manager
Hopefully the issue can be solved asap.
UPDATE 2:
The same person gave out another statement in midnight,here it is:
The Gmail outage that affected many consumers and Google Apps users worldwide is now over. Users should find that they’re able to access their email now without any further problems.
Before you can access your Gmail, you may be asked to fill in what’s called a ‘CAPTCHA’ which asks you to type in a word or some letters before you can proceed. This is perfectly normal when you repeatedly request access to your email account, so please do go through the extra step – it’s just to verify you are who you say you are.
The outage itself lasted approximately two and a half hours from 9.30am GMT. We know that for many of you this disrupted your working day. We’re really sorry about this, and we did do everything to restore access as soon as we could. Our priority was to get you back up and running. Our engineers are still investigating the root cause of the problem.
Obviously we’re never happy when outages occur, but we would like to stress that this is an unusual occurrence. We know how important Gmail is to you, and how much people rely on the service.
Thanks again for bearing with us.
Posted by Acacio Cruz, Gmail Site Reliability Manager
I believe no one want to see this kind of issues to come again because it does brings tons of inconveniences to the users.I think Google should try their best to investigate what causes the occurrence and how to avoid it.Please do things right!