What is the fine-grained topic of the following text: On November the 16th, Vodafone launched their “Infinite” mobile phone plans which they said are a viable alternative to a fixed line due to offering unlimited calls to fixed and mobile phones at a cost of $45 per month; however Optus alleges Vodafone’s advertising is misleading. Only return the topic.
Vodafone's launch of "Infinite" mobile phone plans and Optus's allegation of misleading advertising