What does "continued relevance" mean? What is the difference between "continued relevance" and...?

What is the difference in meaning between "continued relevance" and "continuing relevance"?

Context:

PraiseThe revolutionary wave throughout Europe in 1848, which began in France in February and immediately spread to most of Europe and parts of Latin America,[18] owed nothing to The Communist Manifesto, but within a year the revolutions collapsed.[19] Subsequently, traditional authorities found in The Communist Manifesto and its contents a good excuse for action against its authors. As a consequence, Marx and his wife were arrested and expelled from Belgium, the German daily newspaper published by Marx in Cologne between 1 June 1848 and 19 May 1849, Neue Rheinische Zeitung: Organ der Demokratie, was suppressed,[20][21] and Marx himself was expelled from Germany and France, and, in August 1849 he sought refuge in London.[22][23][24]

A number of 21st century writers have commented on The Communist Manifesto's continuing relevance. Academic John Raines, writing in 2002, noted that "In our day this Capitalist Revolution has reached the farthest corners of the earth. The tool of money has produced the miracle of the new global market and the ubiquitous shopping mall. Read The Communist Manifesto, written more than one hundred and fifty years ago, and you will discover that Marx foresaw it all."[25] Writing in 2003, the English Marxist Chris Harman described the work, stating that:

There is still a compulsive quality to its prose as it provides insight after insight into the society in which we live, where it comes from and where its going to. It is still able to explain, as mainstream economists and sociologists cannot, today's world of recurrent wars and repeated economic crisis, of hunger for hundreds of millions on the one hand and "overproduction" on the other. There are passages that could have come from the most recent writings on globalisation.[26]

The continued relevance of the Marxist theories found within the text has also been supported by the Marxist academic Alex Callinicos, editor of International Socialism, who stated that "This is indeed a manifesto for the 21st century."[27]

Writing in The London Evening Standard on 23 April, Andrew Neather cited Verso Books' 2012 re-edition of The Communist Manifesto, with an introduction by Eric Hobsbawm, as part of a resurgence of left-wing-themed ideas which includes the publication of Owen Jones' best-selling Chavs: The Demonization of the Working Class, and Jason Barker's documentary Marx Reloaded.[28]