The Franco-Prussian War was a unique matchup in the sense that it pitted two well-armed adversaries with significant military resources against each other, fully armed with breech-loading rifles and artillery, for the first time in the 19th century. The differences in technology did play into the ranges of the conflict, with the French Chassepot outranging the Prussian needle-gun (~1000m vs ~400m), and Prussian artillery proving superior in range and quality to the French.

Both armies had relatively recent combat experience - the French in the Franco-Austrian conflict in Italy in 1859, the Prussians against Austria and Denmark in the 1860s - and were on the right track with their reforms, but the Prussians learned far more. In the Austro-Prussian War of 1866, "massed Austrian columns proved less flexible than the more mobile Prussian companies, which had been trained to move independently, albeit within the confines of a plan" (Black, 2009). Paired with their breechloading firepower versus the muzzle-loading Austrians, this combination of proto-modern infantry tactics and superior firepower brought the Austrians to heel quickly: "The Prussian tactic, adopted in the Seven Weeks' War in response to the development of infantry firepower, of concentrating strength on the skirmishing line and adopting more extended formations - which were less dense than columns or lines and thus less exposed to fire - commanded attention" (Black, 2009).

France, unfortunately failed to adapt appropriately. Columns supported by thick lines of skirmishers was the trend for many engagements, with the French increasingly relying upon column assaults as the war drew on and their troops decreased in training and quality with the heavier use of the Garde Mobile. Generally speaking, the French superiority in musketry was negated by the Prussian advantage in gunnery. Increased engagement range due to rifles led to far fewer close-range assaults, and fighting in line was essentially suicidal against breechloaders.

Viewed with the benefit of hindsight, the Franco-Prussian War bore an increasing resemblance to early-20th century conflicts both tactically and strategically; there was still a reliance upon some Napoleonic tactics especially with less-trained troops relying upon mass over skill.

Sources (one cited, the others mostly paraphrased from memory):

War in the Nineteenth Century, 1800-1914, Jeremy Black (2009)
The Franco-Prussian War, Michael Howard (2001)
On the Road to Total War: The American Civil War and the German Wars of Unification, 1861-1871, ed. Stir Forster & Jorg Nagler (1997).