I've been following Skyrim news as much as possible but have seen no mention if this Oblivion feature is still present. When you wear armor is the effectiveness (damage, duration, etc.) of spells negatively affected? And if so, are there perks which lessen or negate the penalty?

Heavy Armor reduces mana regen.

If a mana regen penalty is the scope of the negative effect for armored spellcasting then I approve. Any other information available?

Magicka... Thats all I'm contributing to this XD

It may still reduce the effectiveness of spells, but nothing has been said (outside of an article implying cloths - light - heavy for high - low magicka regen).

I'm going to suppose that +Magicka regen is an available enchantment effect, but still the choice of armors for my mage will be more interesting regardless. Thanks for the info.

So in such cases why need robes for mages?
In Oblivion at last clothing doesn't affect your Spell Effectiveness what certainly was powerful at high levels for example with Spell Effectiveness 100% Frenzy affect actors beyond 25 level if magnitude is high even if spell descriptions still say thats spell affect only up to 25 level but if Spell Effectiveness was less then 100% then actors was not affected by spell.
Magicka regeneration rates can be miserably affected by armor penalties, will be good if if penalty will be more significant.