I've been getting 40+ a day pretty consistently when I'm involved in either a list swap, paid ad, or giveaway.
The reason I've almost doubled that today is because I'm doing 2 of these things at once:
-Taking part in Willie Crawford's JV Giveaway (Only 20 opt-ins from that... Would've shattered my record if I would've gotten yesterday's 45 opt-ins from it)
-Taking part in a list swap with a new JV partner (43 opt-ins from that)
-The rest came from search engines and a couple affiliate sales