1. Each attribute starts with 1 point already assigned, and there are 21 points that you can then assign yourself. Now, since there are 7 attributes, that means that, if assigned evenly, each attribute will have an average score of 4 (21/7=3 3+1=4). With a cap of 10, players will have to make some tough choices (I strongly suspect one of the first mods will be a mod that gives you additional attribute points - of course one for those that like to play god-like characters, but also one for those that want at least a 5 in each attribute, so gives you 28 starting points - instead of the 21).
2. Strength - pretty much unchanged. Raw physical power. Affects how much you can carry, and the damage of all melee attacks.
3. Perception - fairly close to normal. Environmental awareness & "sixth sense" (whatever that means), and affects weapon accuracy in V.A.T.S.
4.Endurance - Here is a change - confirmation that sprinting is in the game. A measure of overall physical fitness. It affects your total Health and the Action Point drain from sprinting.
5. Charisma - Possible changes - Your ability to charm and convince others. It affects your success to persuade in dialogue and prices when you barter. (Now, while it used to help increase your Barter and Speech skills, this may indicate that it is now more powerful in its influence - but I could be wrong).
6. Intelligence - BIG change - A measure of your overall mental acuity, and affects the number of Experience Points earned. (Since when did Intelligence affect XP?? I enjoy playing highly intelligent characters, who are slow to level. This will may make that impossible).
7. Agility - Possible change - A measure of your overall finesse and reflexes. It affects the number of Action Points in V.A.T.S. and your ability to sneak. (Just as Charisma - this could just impact the skill ranks, or it could be and indicator of a much larger influence from the stat itself).
8. Luck - BIG change - A measure of your general good fortune. It affects the recharge rate of Critical Hits, and your chances of finding better items. (Recharge Rate of Critical Hits?? That makes the Critical Hit "Execute Now" button make a lot more sense. Instead of Crits being something that happens on a rare occasion, Crits are now on a timer. You have to wait for that timer to "charge up", at a rate based on your Luck score, before you can activate it. Then, you have to wait for it to recharge. Perhaps you can store one or more up...but I doubt it. This is a MAJOR change. Not sure how I feel about it).
I would post some pics of the video showing the S.P.E.C.I.A.L. descriptions, but due to my low post count, I can't post external links yet. Just take a look at the E3 Video and pause it as they spend the points and you will see what I am saying. Of course, these things could all change before release, and this is all speculation based on information in the E3 Trailer. I could have misinterpreted it, or it could be implemented in a way that I am not quite representing correctly.