Initially I was a bit worried about whether I'd be able to jump straight into the new hardmodes, as I hadn't replaced any of my Dread Guard gear while levelling, but as it turned out it still served me just fine at the new level cap. I'm really pleased with how smooth Bioware kept the gear curve into the expansion, with only a slight stat bump in gear progression once you move into the new content. Of course once you move into the new endgame you do start to see upgrades, but that's how it should be in my opinion.
Having had a chance to see all of the new hardmode flashpoints on live, most of them twice, I'm not entirely sure what to think of them. Even though they aren't new content per se, most people will have run them only a couple of times before while levelling up, so they still feel fresh and new.
They've all had a bonus boss added that doesn't exist on normal mode (or at least didn't until now... I haven't checked whether they added the bonus to the low level versions as well with 2.0), and in the process Bioware has shown that they've learned a lot from previous player behaviour towards bonus bosses - that is to say, most people never bothered to do them on hard difficulty because they usually required going through multiple steps of clicking on various consoles for which you had to kill lots of extra trash, then you'd usually overlook a vital clicky thing somewhere and have to go back, and all of that for a pretty unappealing reward in terms of drops. The prerequisite for each of the new bonus bosses is just a simple straight-up "kill x mobs" quest, which requires you to kill a bit more trash than you absolutely have to, but not excessive amounts, and the loot drops from the bonus bosses are on par with what you get from the end ones - well worth your while!
In terms of difficulty I'm not entirely sure what to think. My full guild groups had some deaths and wipes for sure, but then it was always obvious what had gone wrong. (Usually the healer was still busy bioanalysing something in the last room while the tank was already charging into the next pull. /cough) From a healer's point of view, I felt that the amount of damage going around kept me busy, but wasn't unreasonable. However, it's hard for me to tell how much of that was due to my guildies playing well and being on the ball with CC and interrupts. Most pulls didn't strike me as needing a massive amount of control, but every now and then there would be an absolutely deadly one that I could see being a nightmare in a pug (mostly any pull with a large number of dogs in it - if you don't stun and/or dispose of them quickly, they'll eat your tank for breakfast).
Knockbacks don't always have to be a bad thing.
All in all, those first seven runs were pretty fun, even though there weren't that many changes in terms of mechanics compared to normal mode. Just seeing the new bosses was fun (who doesn't love giant lobels), and at least a few fights offered interesting new challenges (such as how you have to trap the droid on the first boss in Cademimu). Gearing up seemed to go pretty quickly as well (though I got luckier than most I'll admit), and you really notice the difference it makes that the drops will always be something suited to the classes in your party - though that doesn't prevent you from seeing, say, the exact same belt drop three times.
The only thing that concerns me a little is the fact that there are only four of these endgame flashpoints right now. As fun as they may be the first five times around, I can see them getting old quite quickly if that's all we've got to run for our gearing needs.