Robert_Charlton - 8:16 am on May 25, 2012 (gmt 0)
Not all social button bars are equal. Some are notoriously slow. There's one in particular that I've encountered which has a very bad rep. I won't mention the name publicly... but I've seen that removing it noticeably improved loading speed... and fixing that and cleaning up a bunch of other page speed problems (along with duplicate content issues on the site) is resulting in steady improvement in traffic.
I've never just removed social media buttons by themselves, so I can't comment on the effect of fixing those alone. Many sites I've reviewed have had humongously large images and way too many http calls, and cleaning up those problems definitely helps.
Check this thread for several page speed tools, etc, which can be extremely helpful in checking out what's happening....
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