It might be good to personalise this and add the people's actual data towards the top of the message:
Your current status for is:
Confirmed: NO Category: Accommodation: Arrival date: Departure date:
... but we'd still need a (shorter) general announcement, as people will claim this went into their spam folders / went to an email address they don't bother reading.
Subject: Confirm your attendance at DebConf11
We are now starting the confirmation period for DebConf11. It is important for us to know final numbers soon, so unfortunately if you don't reconfirm your attendance, and fill in your travel dates, before the deadline, you won't be counted for food, accommodation, t-shirts, proceedings, etc. Also, you will not be eligible for food or accommodation sponsorship.
If you have registered as a Professional or Corporate attendee, we also ask you to please make the corresponding payment during this period. Other attendees are welcome to make a donation towards the costs of DebConf, if possible. See below.
To reconfirm, you need to login into your Pentabarf account , and tick the "Reconfirm Attendance" box. You must also fill in the dates during which you will be present at the conference. Please also look the other data and fill in anything you missed earlier, or correct the data if your plans have changed. (For our records, please remember to fill in your country.)
You must have arrival and departure dates filled in, or you won't be counted. Please tell us the times you expect to arrive at *Banja Luka*, and when you plan to leave the conference. If you want to arrange group travel to/from the conference, use  but please still fill in your final Banja Luka arrival times in Pentabarf so we know when to expect you, and when to have rooms ready for those staying in the sponsored accommodation.
Please, *PLEASE*, do not reconfirm your attendance unless you know for sure that you are coming to DebConf11. If you reconfirm but then don't come, this will be counted against you for the next DebConf's sponsorship decisions. Of course, if you reconfirm and end up not being able to come, cancelling soon is much better than not telling us.
If you are waiting to know if you'll be granted travel sponsorship or not, then please wait until you know for sure that you are coming before reconfirming -- if the deadline comes and you still don't know because of this, please send us a mail to let us know.
The reconfirmation period ends on Sunday 3 July.
In Penta you will find a "Room preference" box which will allow you to enter whom you would like to share a room with or you would like to be near. Even if you don't have any particular preferences, please state if you smoke/don't smoke, snore/don't snore, etc.
Attendance fee and donations
If you are attending as a Professional or Corporate attendee, or are attending DebCamp without a specific workplan, we ask you to pay your attendance fee before Friday 1 July.
We also encourage anyone who wants to help make DebConf a success to make a donation towards the costs of the conference. You can choose to register as a Professional, or make a donation of any size.
You can make payments in EUR (through FFIS) by bank transfer or USD (through SPI) using a credit card . There are also other payment options available. Be sure to select the right category for the payment (attendance fee or donation).
The Corporate attendance fee is EUR 1000 per week. The Professional attendance fee is EUR 450 per week. Please contact firstname.lastname@example.org if you have any questions.
If you chose "Sponsored registration" for DebConf, but are coming to DebCamp without a specific work plan, we ask you to please pay for your DebCamp food and lodging by paying EUR 450 for that week.
If you have any doubts regarding how much you need to pay, please mail email@example.com.
We look forward to seeing you soon in Banja Luka,