visualCurrentIndentBlock.vim

function! VisualCurrentIndentBlock()
    let current_indent = indent('.')
    let current_line   = line('.')
    let current_col    = col('.')
    let last_line      = line('$')

    let start_line = current_line
    while start_line != 1 && current_indent == indent(start_line - 1) 
        let start_line = start_line - 1
    endwhile

    let end_line = current_line
    while end_line != last_line && current_indent == indent(end_line + 1)
        let end_line = end_line + 1
    endwhile

    call cursor(start_line, current_col)
    normal V
    call cursor(end_line, current_col)
endfunction

nnoremap gi :call VisualCurrentIndentBlock()<CR>
onoremap gi :normal gi<CR>