WordPress 2.7 Problems page not saved, page ranking

Since I have installed new version of wordpress there are problems. Common problem when i hit save the page says “page can not found” sometimes it does save, i keep on hitting refresh button sometimes 20 times to save the page i edit because if i will press back button the post will lost.
Another issue i noticed is that since the day i have installed it my page rankings on google has been lessened. If there were average 100 daily visitors now there are only 10 i dont know whether its the reason? has anyone faced the same problem?