Overall, yes, Madara is more talented, but it's not like it's by such a huge margin. He obviously has more chakra, and on top of that it's more powerful. He's, from what we have seen, the most versatile in weaponry, having seen his stash in the cave, but that's probably negligible. When it comes to the Sharingan, they both can use Susano'o, but Madara is the only person whose eyes are able to differentiate clones from real people, and we've never seen his Mangekyou techniques, probably because that would have made him more powerful than he already was. When it comes to intelligence, they are on the same level, although people will confuse Itachi's wisdom as intelligence and give him the win here, which is wrong. Basically, in every relevant category there is for natural talent, Madara will match or exceed Itachi.