Anybody experiencing decline in traffic

[digital.laugh]

Hi all,

I've been using vBulletin for a couple of years now.

All was going fine, but since last 4 days, the traffic has gone down by 50 - 60%. I rank very well for my main keywords, but have lost out on a few long tail keywords.

All the long tail keywords are pushed to the second page.

Some of the changes I made to my site, before I started experiencing the decline in traffic are:

1> Implemented 'Facebook fan page' in the header and facebook / twitter / +1 in widgets which was placed to the left of the website.

2> I'm still on 4.1.3 and haven't upgraded to 4.1.4

Is anyone else experiencing similar problem ?

Not upgrading, can it be the reason for me to lose traffic.

What's a mystery is, when I compare my previous weeks traffic to my this weeks traffic for the main keywords, it shows 20 - 25% decline, but when I personally search across various Google center, I rank number 1 for the main keywords.

Do you think it's a possible hack or some thing similar ?

Please advice me.

Thanks.