We just released a new application for the BlackBerry Bold called 'Wonderful Remote'. It allows your 'berry to control a TiVo over wifi. Please check it out, its available from wonderfulremote.com.

There is an evaluation period where you can use the application for free. If you like it you can either write a review/blog post about it to get a license free of charge or pay a small fee ($2.99). Further details are available at wonderfulremote.com
best regards,
--Frank