Ok, I have to add my opinions here as I have used both BB and Netflix for 2-4 years.
Netflix is better, period. At one point I had 4 accounts with them years ago, 8 at-a-time and 99.99% of them played/read fine. Once out of every 200 or so I may get one that won't.
Netflix also has MORE in their catalog. If anyone doesn't believe me, research it. I know from reading and I know from renting.
One reason I know they have more is one time I tried to get a couple tv series from BB online but they were all on "short wait", "long wait", "very long wait" and a category I made up: "forget-about-it". I did this with literally 20+ discs. When I checked the same titles on Netflix, they had all available but one or 2 short waits.
First 2 times I tried BB online, I got 3-at-a-time. The last time one was cracked, the other was the wrong title (wrong disc in sleeve) and the 3rd was correct. Not very good for a trial offer.
I currently have 2 accounts with Netflix and I may get a bad or broken one every other month with 8-at-a-time, it's that good. Rarely do I get the wrong one.
BB Online is good for speed because of the store thing. However there are times when they don't give credit/ship another for 2-3 days...which is the same as mail time. The way I do this is:
New Releases: BB Store 10 am Tuesdays
Netflix: TV Series (especially old ones) and other titles, including hard to find ones.
BB Online: For speed only on old and hard to find ones.
I also use either online one to find one if the store doesn't have it in stock. If anyone says BB is better and has more in stock, sorry but it's inaccurate.
The following are quoted from each company's website. Even in the "About Us" it states Netflix has more titles:
Netflix, Inc. (Nasdaq: NFLX) is the world's largest online movie rental service, offering more than 6.7 million subscribers access to 80,000 titles.
Source:
http://www.netflix.com/MediaCenter?id=5384
Our online DVD library has more than 75,000 titles, and it's growing every week.
Source:
https://www.blockbuster.com/signup/rp/howItWorks
But as I said, I've been with Netflix for 3-4 years now consistently and the only reason I have BB online now is because of the store thing.
If/when the BB stores are trying to get customers again, last time if I gave them my address part of my Netflix envelope, I got a free rental for each one. Now THAT came in handy!