For just a domain (with no webpage and no incoming links), 100 uniques a day is what I would consider to be decent traffic, but not necessarily high traffic. It also depends what type of traffic you have. Typo traffic tends to be more focuses than generic domain names. In my opinion, your click through rate for typo traffic tends to be higher than generic domain names (where you may be getting lots of surfers looking for different things). Any parked domain getting over 10 uniques a day probably will turn a profit on the year just through ad revenue. (70 uniques a week, assuming a 10% click through rate at 10 cents=7 clicks X 10=70 cents X 4 weeks= $2.80 per month)
I would consider anything over 1k uniques a day to be high traffic.