I'd rather just "unlimited (note: OK, you can't actually download the whole Internet)" or something like that if you want to get really picky. It conveys the right message while still providing needed information to slower readers.
If so, change your behavior!
At the he.net fremont 1 location, at least, you can buy a full 1000Mbps pipe and run it flat out for $700/month, if you get in on the special. (The old standard price was $1000 for the same thing.) At least at that location, you are paying a lot less than $4 per megabit. (from what I've seen, paying on the 95th percentile usually doesn't make sense, as you get radically lower prices if you buy by the gigabit.)
From what I've seen of other locations around silicon valley, $0.70 per megabit is a pretty low price, but $4 per megabit? if you are buying more than a gigabit, that's a relatively high price. (I mean, you can reasonably pay that much, but you are approaching 'premium' pricing, something that a large IT shop is much more likely to do than a VPS provider.)
And then explain to your customers that 99.9% of them use less than 5 Terabytes/Month bandwidth, and that effective now, the first 5 Terabytes/month of bandwidth is included in the cost of their VPS, and for those 0.1% of customer who exceed that 5 Terabytes, they'll get a very reasonable rate of $0.01/gigabyte ($10/Terabyte) for inbound data in excess of the 5 Terabyte initial allocation.
Realize that linode is probably paying less than $4/megabit @ 95th percentile - but the vast majority of that is likely downloaded, so they have an asymmetric allocation that they are trying to utilize with this "unlimited inbound" offer.
I just want the HN audience, in particular, to realize that the statement ""This means you can upload an unlimited amount of data to your Linode without having to pay for any of the incoming data transfer."" should not be taken at face value if you are putting together a business plan.
In general - bandwidth is priced @95th percentile on the internet, and any time you run into the phrase "unlimited" you should take it with a grain of salt and get something in writing before you rely on it.