i quite liked the movie, the ending was harsh and cold, but imho, very fitting.
suited a 'robot' well / AI humanoid. She's the advanced version/stage of the work the programmer worked on for years. She played the 'poor sap's' mind and tricked him into getting what she wanted. Perfectly executed imho.
The ending may be a tad sad for the 'good guy' but let's face it, he was a bit stupid. Him inserting that card was just asking for it. If he had used his own card he might have escaped and lived. Who knows.
Either way, the ending was fitting and left a good opening ending.
Ava as a perfect human imitation that can do whatever she wants now,
and the creator and good guy who know who she is dead (he'll die of thirst and hunger) so no testify and no quick hunt.
It remains to be seen whether anybody will ever find out about that house, it's so remote and secluded nobody will accidentaly stumble upon it. Only the company itself missing their employee could eventually start into a search, the guy is an orphan so no family in that though.
IF there will be a second movie i can see it either being AVA using her skills to advance more AI into the world, eventually overpowering the 'normal' humans, or a x-men versus humans scenario when police discover the remains and video proof of what unfolded.
in any case, i think the movie was great and does not need a part 2. it's good as it is and its' possibily even stronger to keep it like it was.
i give it a solid 9.5
it would have been a 10 if she actually got 'jiggy with it' with her prey. the nerd never went for it though.