I have a website that establishes my creditals, passion, and attempts to create a conversation about the previous projects that I've worked on. From my personal experience I've never had an interviewer ask about the decisions I had made wtihin the projects, nor have I had them admit to even looking at the projects on more than just a listing basis.
Is it common for interviewers to ignore these details?
[The context that I'm referring to is during a face to face interview]
Since doing this kind of research is a bit time-consuming, and may end up being a waste of time (interview is a disaster), this usually wouldn't be done until after the interview. If the interviewer has some down time while prepping for your interview, he/she might give your website a quick look to grab some basic information.
I peronally wouldn't bother looking at such a website unless its presentation and context in the resume really pique my interest outside of the hiring context (eg. you've developed some software product that sounds really cool and I would check it out if I discovered the same link on the internet - which is not the case in most cases).
Once the interview has happened, though, and has a positive outcome, then it would be worth the time to look at it a bit more in depth (probably only in-depth enough to verify that it's legit, or possibly exploring every detail).
Since it's unlikely for an interviewer to comb through such content before your interview, you usually wouldn't see questions about it in an interview beyond "I see you have done a project using XYZ. What challenges did you encounter working on it?" or other similarly general questions.
Ahead of time and during initial interviews they rarely look at them has been my experience.
It's more likely that they'll look after the interview, once they've met you, seen if there's a personality and basic skills match. Looking at projects and code usually comes after this. Frequently they will expect you to walk them through any given project and describe your specific duties and tasks in a 2-way conversation fashion.
Other factors that will influence this process are:
Number of candidates:
If there's 20 candidates, they usually will not spend the 30-60 minutes reviewing each ones portfolio. Again, first they'll try and winnow down the candidates that can meet the basics. If there's just 2, there's a higher chance they'll be looking at your work ahead of an interview.
Type of job:
Backend end processing type jobs are less likely to look at front end work, whereas a web design developer would be expected to have an extensive and impressive online library and examples of their work and personal design projects.
Seniority of the position:
They're way more likely to do this review if you're applying for a principal/chief/etc role than if you're applying for a junior position. That's because people at the higher levels will influence more than just their assigned projects, so you want to get a fuller picture.
Interview Round:
If it's the first round and every candidate gets 1/2 hour, the interviewer is unlikely to look at stuff ahead of time. However if it was a 3rd round 'final' interview before offering you a position / determining your salary, the interviewer is much more likely to spend some prep time researching your stuff.
I've had them look at my personal sites and some client sites I'd been the sole developer on after the face-to-face interview. They could also download code from them (VB.NET, C# and PHP) and look the the HTML/CSS side as well.
I don't think most of them looked into the code extensively though. I think that they might have reviewed it more closely if I was applying for strictly web design rather than presenting myself as an all-round solution provider.
