Copies selected text, converts to titlecase, and then pastes into OmniOutliner as new row. Comment out line 16 to keep focus on document from which text originates. Change "txt_capped" to "txt" on line 18 to disable titlecase convert. Use Alfred or other manager to link script to hotkey.

paste-to-OO-as-titlecase.scpt

tell application "System Events" to keystroke "c" using {command down}

-- if OO document is minimized unminimize
tell application id "com.omnigroup.OmniOutliner4"
	if miniaturized of front window is true then
		set miniaturized of front window to false
	end if
end tell

-- send clipboard text to handler
set txt to the clipboard as text
set txt_capped to titlecase(txt)

-- identify current row, make new row from clipboard, then select the new row
tell front document of application id "com.omnigroup.OmniOutliner4"
	activate --comment out to keep focus on copied text
	set parent_row to «class OOpa» of last «class OOsr»
	make new «class OOrw» with properties {«class OOtp»:txt_capped} at end of parent_row -- change "txt_capped" to "txt" to remove titlecase
	«event OTREisal» «class OO+s» of last «class OOsr»
end tell

-- capitalize first letter of each word
on titlecase(txt)
	return do shell script "python -c \"import sys; print unicode(sys.argv[1], 'utf8').title().encode('utf8')\" " & quoted form of txt
end titlecase