I've recently been using Expensify, and I've been pretty happy with that as well. It has the ability to take a photo of a receipt from my iPhone, or I can forward email receipts to the system that get loaded into my account, or pull from my credit card.
Honestly, it has cut down my expense reporting time down by a factor of at least 4-5. I'm pretty happy with it.
I was able to put together my expense report on Tuesday on my way from the office to the airport with receipts. The whole thing took me 20 minutes, and only that long because I was over 3G and not wifi.
It's free for individuals, and costs $5/submitter each month once you have more than 2 submitters.
I've been pretty pleased with it. And it's a huge improvement over systems I've used in the past.
As for the privacy aspect, I think the benefits of credit card integration far outweigh the negatives, especially in this day and age of CC fraud protection. I don't have my debit card linked to it, mainly because I centralize expenses on my Amex, but even if I did, I wouldn't mind. A quick phone call to my banks would have all charges immediately reversed pending investigation if I noticed any unauthorized activity. So I really think there is minimal risk of providing this information to realize the full benefits of the platform.