How to subscribe users to multiple lists - workaround
If you are using subscribe.php and want to add users to multiple lists, but don't want to show the checkbox list options on the subscribe form, here's a workaround for index.html
<input type="checkbox" name="list[]" value="LIST_ID1" checked="checked" style="display:none"> <input type="checkbox" name="list[]" value="LIST_ID2" checked="checked" style="display:none">
Replace LIST_ID1, LIST_ID2 with the id's of each list you want them added to. I use this method as follows:
I have a main Autoresponder list but sign people up with different giveaways (e.g. ebooks 1, ebook 2 etc).
In List 1's "Thank you for Subscribing" email, I attached ebook1 - this is a one-off email.
In List 2, they are added to the autoresponder which starts a day or two later.
It's a workaround way to "segment" your lists if you ever wanted to send a specific email to those who got ebook1, but still have them subscribed to your main AR. It also means you can have just one Autoresponder list instead of having to create an AR for every list you have.
Hope this helps.