Do you think Google +1 and Facebook Like are really important for the website...? Not every top 10 site got it....Or just in case Google change its policy and algorithm in the future...
If you are writing relevant content (content that people are likely to find useful and share) then I definitely suggest it . Especially because its not that difficult to integrate.
I haven't been able to quantify the advantage of G+1 yet. Because I only jumped on that boat a bit later.
But I definitely do see a small increase in traffic due to FB Likes