Runbox vs Gmail: Is Google Taking Over?

A few years ago, I wanted a robust email service for my domain name.  After comparing several alternatives, I picked Runbox.  It has a lot of great features - virus protection, spam filter, very large email limits and it collects email from other sources including Gmail, Hotmail and my ISP's.  I have been very happy with it and it has never let me down.  But now, Google offers Gmail for domain names - and it has a free version.  After comparing the two, Gmail has a faster webmail interface and has better IMAP support.  Plus, Google backs not only incoming email, but outgoing email too, even if you use another program to send it (like Outlook).  And, all your email is instantly searchable via Google desktop search.  With all that, I have to wonder, will Google eventually take over?