Google’s share val­ue has hit an all-time high, calm­ing Wall Street jit­ters about the search giant’s abil­i­ty to adapt to mobile inter­net access and social networking.

On Mon­day, Google shares soared by $15.39 to $749.38, a new pin­na­cle rep­re­sent­ing a mas­sive 30 per­cent ($75 bil­lion) rise to its stock mar­ket val­ue in just three months.

The news will doubt­less cap­ture the atten­tion of the inquir­ing search engine mar­ket­ing spe­cial­ist and busi­ness devel­op­ment man­ag­er.  Despite indus­try con­cerns about the Do Not Track fea­ture recent­ly announced for a forth­com­ing Chrome brows­er, the firm’s online adver­tis­ing sales appear to be in rude health.

Out­fac­ing the mobile and social net­work­ing competition

The year has not been plain sail­ing for the search leviathan, how­ev­er, as it faced sig­nif­i­cant encroach­ments into its mar­kets by a coterie of big inter­net firms such as eBay, Ama­zon and Price­line.  The finan­cial melt­down of 2008 also hit Google hard, trig­ger­ing an adver­tis­ing famine.  Although search even­tu­al­ly proved to be a robust form of adver­tis­ing dur­ing the reces­sion, the rise of social net­work­ing and the mas­sive switch to mobile have com­bined to fan investor fears that their low­er adver­tis­ing costs would erode Google’s core business.

The fears aren’t with­out foun­da­tion – recent data sug­gests that almost three quar­ters of SMEs in the U.S. are plan­ning to increase or main­tain their cur­rent mobile adver­tis­ing spend over the com­ing year, with 30 per­cent plan­ning to increase it.  Between 2011 and 2012, spend­ing on mobile adver­tis­ing in the U.S. surged by a colos­sal $1.17 bil­lion to $2.4 bil­lion.

The impor­tance of dig­i­tal dis­play advertising

But Google’s acqui­si­tion of Dou­bleClick four years ago and its sub­se­quent push into the online dis­play adver­tis­ing mar­ket has been pay­ing off hand­some­ly, to the extent that inter­net ana­lyst “eMar­keter” fore­casts that Google is set to become the biggest dig­i­tal dis­play firm of the year, top­ping Facebook.

For its part, Facebook’s recent ral­ly in stock val­ue went into reverse on Mon­day, falling by 9 per­cent.  The fall may be con­nect­ed with media ques­tions fol­low­ing a recent report in the British Finan­cial Times on Facebook’s courtship with a con­tro­ver­sial data com­pa­ny to enhance its adver­tis­ing val­ue, and an assess­ment from Barron’s which sug­gests that its share price remains overvalued.