^^To shorten: when there's million bucks on the line, you don't screw around, you go for tried and tested (albeit boring because they're seen so much) tactics:P
I've been using lothar's a lot lately (since blink or windwalk on SF discussion), and it's extremely well rounded item, giving small nuke and escape skill in one slot for not too great cost. Almost all heroes can benefit from it, and it won't be really countered in public (generally low-coordinated) games.
Regarding huge changelog, i've come to conclusion that devs maybe want to shake metagame a lot, i haven't watched lot of pro games lately, but i had a feeling it's been stagnant for a while.some of buffed heroes haven't been changed quite a while, and they were less viable because they weren't evolving with the map. Couple of small buffs can easily bring neglected hero in the spotlight. For example, back in 6.3x days, Leshrac had 14 starting str and was considered mid-low pick, his str was buffed to 16 and he became one of standard competitive picks after, simply because perception of him changed, not because of 2 more starting strength.