Latest 6.5 MightyRom has the working version of contacts where you can create a "messaging group". I've been waiting to get that in my Touch Pro roms too.
In contacts, you select New, then Msg group. Give the group a name (for ex, I have one for Kayakers, one for Snowboarders and one for current trip we're on) Choose people in your contacts to add to the group and you're done. To send an SMS you choose that group name to send it to and you're set. I'll do screenshots if you'd like some.