I used Free Tax Software last year. Filed my tax return only through this software.
I recommend it again this year.
It is NETFILE certified already for 2008 Tax.
I downloaded it and installed on my desktop. Because I have the 2007 tax return file with Studiotax. I just import 2007 file into it and no need to re-enter the personal information.
Just double check the information and enter my 2008 data.
Now I am waiting my T4 from the company and T5 from bank, HSBC.
I am introduced some Tax preparation software past. Here, and here.
You can download StudioTax here. Please be noticed that CRA start accepting your NETFILE on Feb. 9th.