If you travel by air, it will. During the interview your status changes to Permanent Resident (if you decide to accept your permanent residence during your interview). You are no longer temporary resident or visitor. You don't have an ETA anymore (if u had one before). The airport or even before you board the plane back to Canada will require a permanent resident card that you will get in 8 - 10 weeks from your interview date. The confirmation of permanent resident is not a valid travel document, work permit is not a valid travel document. I would suggest mentioning it during your interview because they do ask about those things. There was a post about it a while ago. The person rescheduled his interview after his travel. If you accept your permanent residence during your interview that will happen before you travel, you might not be accepted back in Canada (even before you board the plane) because you won't have a permanent resident card. I was told in Etobicoke that IT IS NOT recommended to leave the country before I obtain my permanent resident card.
However, there is a solution. If you are staying more than a week in a different country, you can request a Canadian embassy to issue a document for you stating that you are a permanent resident which you might use to go back to Canada.
Landing at the airport is not an option for inland applicants.
I recently travelled outside of Canada and came back 1 week before my landing interview. I was asked those questions and I was asked why don't I have a permanent resident card yet BEFORE I boarded the plane back to Canada.