nice design and what is more important - that keyword might be very expensive in the future (I haven't check its price currently)
nice voip blog. I'd say the look and feel is great. you have all the social bookmarkings needed. I'd suggest to expand out your tittle tag kewords as well as optimizing your words in your categories to help find other niche voip words to work with. good luck, keep on blogging on this niche high paying voip topic.
The logo is not clear. It looks blurred. The menu could use some graphics. The icons under each block… I think those are not very effective. What if you change those to text links.
Good topic and good layout. I believe VoIP is a good keyword for adsense. I am sure it will becomre more competitive