157 characters... ;-)

select *I=*STDERR;$|++;select STDOUT;$_=join('',<DATA>);
s#\[([^\]]*\?)\]#print I"$1 ";chomp($i=<DATA>);$i#ge;
s#\[([^\]]*)\]#@f=split(/\|/,$1);$f[rand@f]#ge;print
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Update: admittadly, I suck at golf ;/

Yet, just now I've learnt an important lesson. The only reason I failed to produce significantly shorter/improved golf code is because I simply failed to think 'outside of the box'. For a couple minutes I simply kept staring at the initial golf piece, in the back of my mind being afraid to temper with it too much as not to break it.

Had I only taking the logic of the code aside and tried to come up with an alternative code of mine, I could have a better chance at gaining significant improvement.

{grin}

Update 1:

Looking at Util's and japhy's golf code and sort of combining the good parts of both, I get this piece 97 characters long:

print map{s/\?$/? /?print(STDERR)&&(<>=~/.*/g)[0]:split('\|')&&$_[rand
+@_]}
map{split/\[(.+?)\]/}<>
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Update 2:

japhy, the golf works fine for me, here's the complete code and source file:

#!/usr/local/bin/perl

print map{s/\?$/? /?print(STDERR)&&(<>=~/.*/g)[0]:split('\|')&&$_[rand
+@_]}
map{split/\[(.+?)\]/}<>
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Source file:

Hello [world|planet|dude|there], [Name?]!
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Hmm,.. but it does appear to print extra '0's when I use the original text. Let me investigate why that's the case ... update: This works:

print map{if(s/\?$/? /){print STDERR;(<>=~/.*/g)[0]}@z=split/\|/;$z[ra
+nd@z]}
map{split/\[(.+?)\]/}<>
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_____________________

# Under Construction
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