Spoilers ahead, by the way, if you haven't played the new ME2 DLC pack "Lair of the Shadow Broker"...
 
The new DLC kinda knocked a big chunk of story out of ME3. Some speculation about the Shadow Broker being Miranda's father is ... well, let's just say that ended up being wrong ;)
 
But I'm wondering about structure. With the new Shadow Broker in place, we're pretty well assured that Liara won't be a squadmate in ME3. But we're also given a potential new hub for activity. Rather than the Normandy, it was interesting to see the Shadow Broker's ship outfitted with, well, just about everything we need for missions. The video archive in particular is intriguing me, along with the "investment opportunities" kiosk. Will the SB's hideout be the new hub, with the Normandy taking on a secondary role? Any thoughts? It seems like some suggestions that Shepard send other operative out on missions might actually have some merit after all...

I think Liara will end up being a villain in ME3.

I think ME3 will have a little more 'thought' to it. As you said, the investment opportunities could turn into an interesting side-game where you dispatch members of your team to complete missions and obtain bonuses(something we've they're adding to Assassin's Creed: Brotherhood, no reason something similar would conflict with the ME universe).  There almost has to be something like this planned - as you've developed or destroyed a TON of relationships along the way to the Reaper showdown - The final fight with the Reapers will be akin to the suicide mission in ME2 - only with your actions from both prior games being taken into account: Will the Krogan join you? If you saved the Rachni they will help, same goes for the Council and probably Cerberus too (though in my case I'd imagine Cerberus isn't gonna lend a hand).
 
Liara will no doubt provide you with vital intel or perhaps even take on the Illusive Man's role as Shepard's 'handler' if your choices have led to that. There's a lot of potential there and hope they do justice to everything Shep has done over the years.
I really like the idea of using the Shadow Broker's ship as a hub, but I have the feeling they won't give an ME game without a Normandy to pilot.

" I think Liara will end up being a villain in ME3. "

I never really thought about it tbh, however i'm sure she's going to help you in mass effect 3 defeat the reapers of course indirectly. There was an option to choose if you will salvage the alien ship in ME2 or not for cerberus, if you chose not to, hopefully liara would help. I don't know, i'm purely speculating here, I really haven't thought about it.

" I think Liara will end up being a villain in ME3. "

who's the shadow broker again? Is he Martin Sheen?

She'll probably drop some side-quests on the main character which'll help fund the war effort against the Reapers.
I highly doubt that OPTIONAL dlc is going to have a massive influence on Mass Effect 3... Unless they assume that what happens in the DLC plays out even if you hadn't bought it - which would make it, redundant?

" who's the shadow broker again? Is he Martin Sheen? "

" @blacklabeldomm said:

" who's the shadow broker again? Is he Martin Sheen? "

Martin Sheen is the Illusive Man. The shadow broker is revealed to be an awesome badass in the new DLC. By the way, was his race or species ever mentioned before the new content? "

" She'll probably drop some side-quests on the main character which'll help fund the war effort against the Reapers.I highly doubt that OPTIONAL dlc is going to have a massive influence on Mass Effect 3... Unless they assume that what happens in the DLC plays out even if you hadn't bought it - which would make it, redundant? "

" @blacklabeldomm said:

" who's the shadow broker again? Is he Martin Sheen? "

Martin Sheen is the Illusive Man. The shadow broker is revealed to be an awesome badass in the new DLC. By the way, was his race or species ever mentioned before the new content? "

I am liking the idea that Shephard will finally get some help with the new Shadow Broker very much, meaning that in ME3 the player may have potentially amazing control in affecting the universe as a whole with the power of information (remember the quote where the new Shadow Broker states "I could start a war in ten minutes" I think was what was said).
 
Also, we need a Yahg squadmate for Shephard stat!  The Yahg sound awesome.

" She'll probably drop some side-quests on the main character which'll help fund the war effort against the Reapers.I highly doubt that OPTIONAL dlc is going to have a massive influence on Mass Effect 3... Unless they assume that what happens in the DLC plays out even if you hadn't bought it - which would make it, redundant? "

I dont think they will take the Normandy away from being the hub of the game, i think the Normandy is a character of its own.

I think she'll be a huge asset for Shephard.  The ship, her resources, her contacts...  I'm sure she'll be able to offer a big help.  Maybe even find out some whole new way to beat the Reapers that didn't seem possible otherwise.

There is no way the Shadow Broker ship will be used as the hub or as a replacement for the Normandy.  The SB has to stay hidden, flying around in that electrical storm or whatever.   
 
Hopefully they just make all the information on the SB's ship available to the player on the Normandy.

Spoilers:
 
I found it amusing (or really not, depends) that the original SB was overthrown by something that was intended to be a plaything of sorts. The myth behind the SB (him being untouchable and god-like) was pretty much destroyed with the DLC. However, I wouldn't say that I didn't anticipate that Shep and co could defeat him. At least we got to be with Liara for a bit.  
 
 
Kind of makes you wonder what was the DLC all about - overthrowing the SB (good reason), getting it on with Liara (good, but not necessary), or something else (can't think of a good reason).

Destroyed? I would say the key takeaway is that it was preserved; not for Shepard, but Shepard for almost everyone else in the universe.