Apparently perks will be capped - probably at 50. Assuming that there are about 15 perks (including upgrades) per skill, then you can get all the perks for 3 skills, and a few perks for another skill. This might suggest that Bethesda is aiming for us to specialise in only three skills - so you can only get 3 skills to 100.
On the other hand, given that skills are loosely categorised into combat, magic, and stealth, Bethesda might take the prototypical character to be one which specialises in all and only those skills from one of those categories. In that case, they might aim for us to get 6 skills to 100. But then you are still faced with a choice of where to distribute your perks - even though you've gotten 6 skills to 100, you still can't, as it were, max out those skills.