It seems there is a lot of controversy over the newest unreleased patch, and in my first listen of the video, I found myself whole heartedly agreeing with the vast majority of commenters (on the forum and the facebook page). But as I kept reading through the comments I started seeing that there could be some good in it.
For the most part, I feel like most peoples' rune pages look similar for similar types of champions. In particular there is a lot of Spell Pen reds and Mana per 5/level yellows, with Quints and blues are subject to change. Very ordinary, very boring, yet very good.
With the new patch coming out mana regen runes will be taking a hit, although (I noticed a few people mention this) it seems that champions' base mana regen will be getting a buff, thereby keeping any vast changes to endgame mana regen very minute. While it is frustrating knowing that the amount of IP that you spent on your runes in the past will probably be somewhere around half as useful as it was then, it is by no means a waste, and this leads me into my next point.
The Doran's items are also taking a hit disallowing the use of both a Doran's item and any kind of health/mana potion. While this is also somewhat frustrating it's neither bad nor good, and will allow some creativity among the players. The changes are static for both sides of the playing field, so you know that any problem you could have, you opponents team may have as well. If a player chooses to have a Doran's item for the bonus health and stats, they lose out on the chance to have health pots and vice versa.
Health Potions heal 200 health over 20 seconds, while having a doran's item gives you an instant bonus 100 health. Health potions will be more useful for longer staying power, while doran's items will give that player the chance to try to take out his/her opponents swiftly with the increased health and stats. A health potion will very rarely be able to outheal some early burst damage, though if the enemy can manage to only takes a few hits, a health potion will be a key choice.
This being said, I move on to the creativity part. Since now you're given two options, to either be aggressive and try to get a kill quickly, or to last longer in the lane, and now that champions with mana will presumably have better base mana regen, you are given the opportunity to change your runes for a different playing style. Mana regen runes, as I stated, will no longer be as useful. So you could switch them out for something that gives you better defensive options or some health regen, grab a doran's item, and have no need for those health potions. Or you could keep the full mana per 5 yellows and have a mana advantage over your enemies, grab some health pots, and have a more secure, less aggressive laning phase. Perhaps there will be more reason to invest in some HP or AP runes as a caster now, to make up for the lack of Doran's item, while grabbing a suitable amount of health potions.
I don't think the changes to the runes are necessarily bad and open the floor to some new ideas to an otherwise stale game, but I'll keep my mind open until the patch comes out and we, the players, find out for certain the state of the game.