Yes, the merging of Blog and BlogMan is still the plan - just not sure when ... but somewhere in the 8.0 release
You can try out PHP even now - all you have to do is either change the file parsing options on your server so that .htm and .html files are parsed for PHP or use the Blog option to set generated file extensions so that you have .php files instead of .htm or .html.
RSS feeds can be created now with a template - see Tyran's exhaustive comments on this matter elsewhere on the forum
Yes, I realize that the date format generated by Blog is not what is needed by RSS but I hope to fix that by giving a new option to the date and time tags where you can specify the exact format you want.
As of Blog 8.0 beta 3 the summary feature should be stripping out HTML tags anyway. So the word count for summary *should be* based on the non-HTML tag version of an entry. Please verify this and let me know if this is not so.