No Cliffhanger not at all. The Mass Effect trilogy is complete. It has no loose ends. 

@ all the others 

Listen to Khuurta he´s right. The ending sucked big times and I hope they´ll fix it somehow but despite all that the game is very enjoyable. 

With the uproar over the ending, I was expecting something absolutely terrible. Instead, what I got was a pretty cool final mission that culminated the relationships made over three games with an underwhelming ending. It was nothing shocking to someone who endured the endings of the first two Mass Effect games.

It's like they wrote a choose your own adventure trilogy only to largely nullify your decisions by having you land on the same final page as everyone else.

As noted, it wasnt that flash to begin with, basically your usual space & guns gung ho style game. I feel sorry for the hardcore fans, but surely you didn't expect too much more? For that nostalgic feeling i'll support Bioware & say you expected too much. Its a star wars (also terrible imo) knockoff trilogy finale for %^%& sake. Not the complete works of Shakespeare or Jane Austen.

On the flipside people who agree with you are now raising money to support changing the ending & there seems to be a few of them, never thought I'd see a game rate lower than Skyrim PS3 on amazon. 2.3 out of 5 average (currently) with over 50% 1 out of 5 ratings, ouch!.
http://www.gameblurb.net/news/gamers-raise-32000-to-change-the-ending-to-mass-effect-3/

I'd almost feel sorry for Bioware if they hadn't, with almost yearly mainline releases, somehow given us a decade of sub par games.

Still its nice to see so much passion over a game story, didnt think the global game community had it in them. i'm actually impressed.

Spoilers follow

So my main problem with some of the endings is that I just can't make sense of them.

A synthesis between human and machines where everyone is suddenly converted to have little green lines all over them? My suspension of disbelief just can't go that far, it's too farfetched.

I also fail to understand why the Geth and EDI die in the ending where you destroy the reapers - they are in no way connected to the catalyst so how does it destroy them?

Maybe I'm missing something...

If they let you down, don't reward them with more money for ending DLC (as if they'd even release that). 

Only 3 endings to the game? Alternative endings are needed to add replay-ability to the game.
I enjoyed ME and ME2. Waiting for ME3 to be reduced in price or the release of the GOTY edition.
I have heard a game save file from ME2 penalises you on ME3 or does not even work.

With players making decisions over 3 games they should really have gone for more personalized endings taking several of the decisions into account instead of just the last decision mattering and then making 3 very very similar ending sequences that mostly differ by the color of the beam....

Ok. I was pretty bummed at the ending like you folks and then I heard about the indoctrination theory and all the pieces started falling into place. Just google ME3 Ending Indoctrination theory for further details..

There have been rumors going around that because of the leak prior to the game, BIOWARE had to change the endings and are actually going to release a dlc WITH THE ACTUAL ENDING called "The Truth" completely FREE OF CHARGE.

Take all this with a grain of salt but I'm more inclined to believing the indoctrination theory because the writers at Bioware are too good to have left such glaring plot holes at the end of ME3, especially when everything before that was so amazing. Also if all this turns out to be true Bioware may have just pulled off the biggest trolling attempt ever.

"The game's ending has been controversial with some fans. Online polls have shown an overwhelmingly negative view of the game's three similar endings. Criticisms include the lack of variation in the endings in view of the player's choices over the previous two games, as well as a general lack of closure and perceived plot holes"
http://en.wikipedia.org/wiki/Mass_Effect_3

It's because they are synthetics, the geth, EDI etc are considered to be the next step in evolution, and will likely turn on their creators - the humans & aliens, therefore the best way to stop the cycle is to destroy the synthetics, the only reason, according to the little boy the reapers came is to destroy the races and help them ascend before they descended into chaos as a result of creation of synthetics.

 The ending could have been more tied in with the options that you've picked earlier during the game, but by the looks of it, these decision can come back to haunt you either during the next iteration of Mass Effect or the DLC.