In 1934, it was called “a record that promises to endure for all time.”
From the New York Times article written on July 13, 1934:
A record that promises to endure for all time was attained on Navin Field today when Babe Ruth smashed his seven-hundredth home run in a lifetime career. It promises to live, first, because few players of history have enjoyed the longevity on the diamond of the immortal Bambino, and, second, because only two other players in the history of baseball have hit more than 300 home runs.
Of course, today, we stand with Ruth as third on the all time home run list and 54th on the games played list. The scientific developments that forever changed the game were unforeseen in the mid-30’s where 700 home runs seemed unattainable unless you were the Bambino. Imagine Ruth slugging in this era where something close to one-thousand bombs would be said to “endure for all time.”
As for the ball that Ruth swatted for #700:
Today a youth was happy and richer by $20. Even before he circled the bases, Ruth was shouting to mates on the field: “I want that ball! I want that ball!” Emissaries were sent scurrying after the youth who recovered the ball after it cleared the fence, and it was restored to Ruth in the Yankee dugout, in exchange for $20.
According to the Bureau of Labor Statistic’s Inflation Calculator, $20 in 1934 has the same buying power in 2013 as $347.68.
In 2005, Barry Bonds’ 700th home run auctioned for $102,000.
Baseball and Things 
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