Here is how l see it.
Linux is good for Linux gurus (who live in the terminal and use vi). lt is also became good enough in recent years for simpleton users who just want to browse the web (watch youtube, write mail...).

But the problem is they are not going to install Linux (or Windows for that matter). Because "I'm just not adept/understand/know...". (not sure how it is in English, i only hear it in Hungarian) Even though they could. Because they all know intermediate users they can ask. And that's where it's at. We intermediate users install maybe 90 percent of the desktops. So if you want desktops then you need to win us over. And you are not...

I'm an embedded hardware/software engineer. When I was young I was playing with OSes (DOS, Win, qnx, OS/2 warp, BeOS...), but now I want to *use* my desktop (for work) and not play with it (maybe play on it). If the OS is not working properly it is preventing me from doing my job, and I'm loosing money (and/or my free time and my sanity).

Linux Desktop (ubuntu) LTS is a joke. WinXP was around for a decade, that is LTS. I don't have time to learn new distributions, UIs... every year. And the ever present or growing inconsistency does not help either.

So who are intermediate users? Basically we can use Google (or Bing, Yahoo). That's it. And when I search for "how to ..." I get maybe 10 percent success rate or even less. Because either the top result is a forum, where the same question is asked but there is no solution, or there are many solutions that none of work, the result is for a different distribution, same distribution but different incompatible version... (RTFM does not help because I do not have time to read 10 new ones every year)

(for example: configure (multiple) static IP on Linux: /etc/network/interfaces right? well that's what it says if you are debian based, not even gonna start with RHEL, but on raspbmc the file is so fucking empty and does not do anything, and on my ubuntu it is also does not contain eth0 (and eth1) because of the network manager. Configuring monitor resolution (permanently), xrandr? edit /etc/X11/xorg.conf? well you mean create one. Would it be so fucking hard to include a sample one in every distribution where you can just uncomment lines? Run something on startup: sys-v init.d, rc.d, upstart, lsb script, service, update-rc.d... Ubuntu 5 had GUI group (and user) management, they removed it since then. Congratulation.)

I could continue, but I have to work now...

Maybe if developers would focus more on stability, fixing bugs and developing useful tools, features we need rather than rewriting everything (Unity, that is useless on VMs)... (I know, it's less exciting to write production quality code than writing something new.) Maybe one day.

I really like the quote I found on Coding Horror blog:

quote from Havoc Pennington:

"It would be wonderful discipline for any software dev team serious about Linux 'on the desktop' (whatever that means) to ban their own use of terminals. Of course, none of us have ever done this, and that explains a lot about the resulting products."

I must confess I'm not a C++ master (more like a beginner).
But I have written code in many languages:
Assembly (x86, x64, AVR, ARM)
asp, asp.net
Basic (think Commodore 64)
Batch script :)
C
C++
C#
Clipper (anyone)
D
Delphi
Java
Javascript
Lua
Matlab
Pascal
Perl
Php
Python
Shell script
VB script
Verilog
VHDL

I have not yet used but I'm interested in F# and Go. (async and concurrent programming among other things)

I think C++ lacks certain features, native data types, and (a feel of) simplicity that other modern languages have.
For example I like Pascal style strings much more where you can determine it's length in O{1} time among other things (return, concate, resize). (same for arrays, where in C you have to pass length separately, and hope you won't cause buffer/stack overflow)
Template meta-programming is a great, sometimes magical tool
(which you can dig your grave with if you are not careful -- debugging, maintaining, understanding, editor intellisense).

I do not expect anyone to start programming in assembly, I wouldn't. Though there are High Level Assemblers out there, (the lack of) portability is a major disadvantage of it.
But I have not yet worked on a processor that had not supported carry flag, and I do not know any way to access it from native C code. (Lets say shifting a 1024 bit integer, adding, subtracting them....) Checking for integer overflow is also a pain in the ass (pre check/post check. And I have not found any way writing my code that would get the compiler to produce the right assembly.) Also on processors I worked on multiplying 2 registers results in a register pair because that't how multiplication works and extends the range of possible results (and this is why there is a carry flag used during addition), but C is blissfully or painfully ignorant of this (depending where you are looking it from) and this is usually where code readability starts going down the toilet when you are precasting integers and alike. (When you need to multiply two 32 bit int (and maybe then divide it so the result is still 32 bit), but you cast it to int 64 pre multiplication, will it result full 64 bit multiplication (software multiplication on 32 bit processor)?)
But I guess code efficiency does not matter and that is why we have longer response times now on GHz processors, than we had on 486... (and of course because of bling)

Reading code examples about why you need auto in the comments makes me cry. WTF is boost::asio::placeholders::bytes_transferred!? (It was a rhetorical question, don't answer it:)
This is what the improved readable code looks like?

So C is not close enough to hardware to understand it and generate efficient code, and not high level enough to abstract and understand things that humans would like to use naturally. We have to think in bits and clocks to write some broken codes.

I'm an embedded developer so I'm stuck with C (and C++) for now.