Two words to describe the minion changes:

"It can be seen that way, but with all the other changes (minions have more gold, minions also push harder against enemy champions when ahead, towers are weaker across the board) create a gamestate where you have to leverage your advantages as the gap between an ahead and behind team are actually widened further than what you see on live. On the other hand, a team that fails to press their advantage risks minions getting to the enemy base, feeding them gold and XP. However, the team that's ahead can buy the more expensive items, meaning higher chances of breaking a stall or successful dives, picks, etc. TL;DR lots of changes, but not 100% the same"

and

"We're talking about this more in the upcoming Rundown, but the idea isn't to make games more snowbally - in essence, games often hit a point on live where a team's effectively 'won', but has to wait some amount of time starving out the opponents to actually take the nexus. You just kind of starve people out while you wait for the other team to die. This is meant to address that. If games are faster or shorter that's not the goal - however, it says 'are you a winning team? go actually win instead of continuously waiting for jungle spawns and lane minions to starve the other person out. Use your advantage, or the opponent will get some of it back."

--Scarizard

They are trying to break stalls. The winning team has a good opportunity to leverage their advantage, and if they don't then the losing team gets more farm. The part about skipping the starving-them-out phase sounds a lot like forcing a gg surrender you've already lost. I hate it.

for serious

http://boards.na.leagueoflegends.com/en/c/gameplay-balance/eEtYAfoc-new-winions-have-me-concerned?comment=000d

TL;DR: Minion changes not yet active.

I wonder how often I'll have to post this the next few days...