Problems with Cyrillic fonts in XeTeX

Question

I have my document with Russian text. Formerly, it was stored as UTF-8 without BOM and compiled with LaTeX. All worked fine with the following preamble:

\documentclass[11pt,a4paper,final]{moderncv}

\usepackage[T2A]{fontenc}
\usepackage[utf8]{inputenc}
\usepackage[russian]{babel}

\renewcommand{\rmdefault}{cmr} % Шрифт с засечками
\renewcommand{\sfdefault}{cmss} % Шрифт без засечек
\renewcommand{\ttdefault}{cmtt} % Моноширинный шрифт

But some utilities were not able to identify UTF-8 because of BOM absence, so I added it. From now on LaTeX was unable to compile the document, because of BOM. I switched to XeTeX and replaced preamble:

\documentclass[11pt,a4paper,final]{moderncv}

% Resolving "Failed to convert input string to UTF16" error. See http://tex.stackexchange.com/q/66722/24133
\usepackage[unicode,pdfencoding=auto]{hyperref}

\usepackage{polyglossia}   %% загружает пакет многоязыковой вёрстки
\setdefaultlanguage[spelling=modern]{russian}  %% устанавливает главный язык документа
\setotherlanguage{english} %% объявляет второй язык документа

\setmainfont{CMU Serif}           %% задаёт основной шрифт документа
\setsansfont{CMU Sans Serif}      %% задаёт шрифт без засечек
\setmonofont{CMU Typewriter Text} %% задаёт моноширинный шрифт

%\renewcommand{\rmdefault}{cmr} % Шрифт с засечками
%\renewcommand{\sfdefault}{cmss} % Шрифт без засечек
%\renewcommand{\ttdefault}{cmtt} % Моноширинный шрифт

But in this case I got several problems:

1. Fonts are slightly different
2. Italic is missing!
3. Quotes << & >> are not parsed

See image before and after:

How to resolve these issues? I suppose that if I can tell XeTeX to use the same non-unicode fonts as LaTeX, it will help.

Please, advice on all the issues, since I need them all to be fixed.

PS I'm using MiKTeX 2.9 (x64) under Windows 7 (x64).

Update Example for LaTeX, where everything is fine:

\documentclass[11pt,a4paper,final]{moderncv}

\usepackage[T2A]{fontenc}
\usepackage[utf8]{inputenc}
\usepackage[russian]{babel}

\renewcommand{\rmdefault}{cmr}
\renewcommand{\sfdefault}{cmss}
\renewcommand{\ttdefault}{cmtt}

\moderncvstyle{classic}
\moderncvcolor{green}
\name{Михаил \vspace{0.5ex} \\}{Матросов}

\begin{document}

\section{Свои проекты и вклады}

\cvitem{2014}{
    \httplink[\textbf{C++ User Group, Russia}]{meetingcpp.ru}, \emph{Докладчик} \newline{} 
    Доклад \httplink[<<С++ без new и delete>>]{meetingcpp.ru/?p=250}.
}

\end{document}

And example for XeTeX, with the mentioned issues (document body hasn't changed):

\documentclass[11pt,a4paper,final]{moderncv}

% Resolving "Failed to convert input string to UTF16" error. See http://tex.stackexchange.com/q/66722/24133
\usepackage[unicode,pdfencoding=auto]{hyperref}

\usepackage{polyglossia}
\setdefaultlanguage[spelling=modern]{russian}
\setotherlanguage{english}

\setmainfont{CMU Serif}  
\setsansfont{CMU Sans Serif}
\setmonofont{CMU Typewriter Text}

\moderncvstyle{classic}
\moderncvcolor{green}
\name{Михаил \vspace{0.5ex} \\}{Матросов}

\begin{document}

\section{Свои проекты и вклады}

\cvitem{2014}{
    \httplink[\textbf{C++ User Group, Russia}]{meetingcpp.ru}, \emph{Докладчик} \newline{} 
    Доклад \httplink[<<С++ без new и delete>>]{meetingcpp.ru/?p=250}.
}

\end{document}

Answer 1

This is not an answer, but a comment can't contain an MWE and pictures

It would be helpful if you did some more work in diagnosing where the problem occurs. Simplifying your example and compiling the code with XeLaTeX gives no issues for me.

\documentclass{article}
\usepackage{fontspec}
\setmainfont{CMU Serif}  
\begin{document}
\section{Свои проекты и вклады}
\emph{Докладчик}Доклад <<С++ без new и delete>>.
\end{document}