Agreed. I am happy with Heroku so far (I am pre-launch so the effect hasn't been great), and intend to stick with them for at least a while (I might have most of two decades as a dev in this business, but zero of those are as a sysadmin), but 45 minutes is low:
I may be showing 48^ errors in my per-minute checks but those errors occurred in at least^ nine separate blocks across an eleven hour window.
In other words, we are probably looking at around ten hours of issues, even if not outright outage.
^ I disabled the checks at times because it was just a waste, so the true stats are likely worse.
Of course, my point was that 99.9% is expected on even the cheapest setups. Premium hosting like Heroku should at least be able to deliver comparable uptime to a cheap shared host like HostGator.
However, Heroku appears to have no SLA, so its a moot point anyway.
Regardless, 99.9% is really not special or even acceptable from a high dollar host like Heroku. Cheap shared hosts like HostGator can give you 99.9%.
I'm pulling for them, but they've got some work to do.