[N.B. I’m writing here only as an avast! user: I’m not speaking for the company.]
This is more of an adware/spyware problem than a virus problem.
Some virus companies are moving towards an integrated anti-virus, anti-spyware approach: see for example these stories about eTrust anti-virus and Pest Patrol and Trend Micro and Intermute teaming up.
http://news.com.com/CA+set+to+deliver+defensive+packages/2100-7355_3-5751938.html?tag=cd.top
http://www.theregister.co.uk/2005/05/10/trend_buys_intermute/
Other anti-virus companies license a version of an anti-spyware program. Buy F-secure, for example, and you get Ad-Aware Pro.
For the moment, avast! does not offer comprehensive anti-spyware protection, but this simply leaves you free to use the best of the anti-spyware programs available to complement avast!
As most recent reviews suggest that no one anti-spyware program offers 100% protection, even if you purchase a package which provides anti-virus and anti-spyware together, the anti-spyware protection you receive would not be perfect.
To remove spyware, the best approach is to use a number of anti-spyware scanners. As there are free versions of many of the best scanners, using avast! plus these scanners is still a far better solution than most anti-virus/anti-spyware packages.
Some argue that the best result will be obtained by anti-virus companies concentrating on viruses, and anti-spyware companies concentrating on spyware. Others argue that the distinction has to end.
Of course the big advantage for an anti-virus company concentrating on viruses, Trojans etc is that the virus writers are not going to sue them for loss of business. Some of the big companies getting into fighting spyware have found that they are getting into legal arguments with the spyware pushers who claim that their programs are not malware but legitimate software. This has led to some spyware definitions being withdrawn from anti-spyware databases, but also to spyware pushers providing uninstallers for their own products so they can claim to be legitimate.
Apparently Webroot’s SpySweeper works well in cleaning up Aurora. A free working trial is available. I would also recommend running it just to check that Mypctuneup has not left anything nasty behind.
By the way, if what they say about the registration process for Mypctuneup is true, you will be getting some spam in the near future as a result.