Prompted by this thread, I checked my Paypal Credit account and noticed my limit had been bumped from $2,100 to $3,100. I'm an infrequent Paypal user so my limit had been stuck at $2,100 ever since I opened the account in 2005. But recently I've made several transactions of reasonably high value, and just last week I updated my income after getting an e-mail request to do so from Paypal.
