In my view, I don't think it was possible to continue building stories and have the EU be maintained perfectly. Eventually, the only way that can become feasible is if you stop making PT and OT-era stories, and those are among the most marketable books they can write (you can make all the Legacy-era books you want, but those appeal mostly to fans like us; a book set in the months after ANH or during the Clone Wars or before TPM has a broader audience). So, in my view, the death of full EU continuity was inevitable, and so it's better to do a clean cut and name something Legends then to let it slowly die via oversaturation of stories (how many books, comics, kids stories, etc. take place within 1 year of the Battle of Yavin? Imagine how many there would be in 20 years).
And yay, new stories, and even new stories on film! WOO!!!!!!!!
All I'm waiting for is the news of Marvel Star Wars books in 2015. I was hoping for something at C2E2, but so far nothing I think.
I also wanted to address Henning's suggestion to cut at the NJO. I have difficulty with this suggestion for two big reasons:
1- People who haven't read the NJO may find a lot of it easy to swallow (Mara Jade, the Skywalker and Solo kids, Chewie's death, etc.) But there's a lot that pretty insane. If you've never heard of the Yuuzhan Vong, and see Coruscant post-Vongforming, or see a delegation of Vong from Zonama Sekot, that'll be a tough pill to swallow. I think many people will have a "wtf?" moment.
2- I think that line is REALLY arbitrary, and based purely on popularity. A lot of people liking the NJO, but fewer people liking the Dark Nest Trilogy, Legacy of the Force, Fate of the Jedi, and Legacy is both a) not a great way to draw a line, and b) not objectively demonstrable (even book sales don't tell the whole story). Dark Nest wasn't my favourite, but the other two series were fun, and Legacy was AMAZING. I know you need to draw a line somewhere, but basing it on popularity is strange, in my view.
In my opinion, better to do a clean cut after Episode VI. Keep as much pre-ROTJ stuff as you can (but giving freedom to contradict the oldest stuff, like the Marvel and newstrip comics, or the Han Solo/Lando Calrissian adventures, or the Missions kids books, just to declutter 0 ABY), but abandon the post-ROTJ EU. Let it continue having new books if you want, even ones consistent with that era, but labeled Legends.
"I must not fear. Fear is the mind-killer. Fear is the little-death that brings total obliteration. I will face my fear. I will permit it to pass over me and through me. And when it has gone past I will turn the inner eye to see its path. Where the fear has gone there will be nothing. Only I will remain."
-Bene Gesserit Litany Against Fear