One problem with PowerShell is that it uses too much resources for a shell. I believe it to be superior in some ways to Unix shells, but I was never able to get (psychologically) past the 15 second or more startup time needed on my machine (Windows 7 netbook). Given that languages like Python have less starting times, I am likely to use the command prompt and/or scripting language every time.
I guess server people would not encounter this problem.
Good news: the startup time is largely fixed on PowerShell 3 (Windows 8). Most of that startup time ends up being PowerShell trying to load all of the snapins on your system--and you can have a LOT of them if you're a developer, since there are snapins for IIS, SQL Server, and remote management that come more-or-less out-of-the-box in that scenario. PowerShell 3, rather than actually loading all of these, simply notes what commands they export, and only bothers actually loading the snapins if you actually use them. Up side, PS on Windows 8 takes less time to start up. Down side, commands occasionally pause a second while PowerShell loads whatever snapin happens to have the commands you just tried to use. This ends up being a pretty good trade-off in my daily work, though.
I have had some long start times like the parent. Typically it's pretty short. I do agree, though, that not having that instance start time is a bit psychologically confusing... it's a shell, how could it not start instantly! However, typically if I'm developing I'll just leave one open at all times and it's not an issue.
oh wow, now that you mention it you're right ... PowerShell does take a long time to start up. I tend to leave a powershell window open for pretty much my whole session so I guess it's not a huge deal for me. But yeah, when starting up I definitely notice it.
I guess server people would not encounter this problem.