Here are some quick resources if your looking for information around Lync 2013 in a VDI environment:
Update: Microsoft Lync 2013 Preview in a Virtual Desktop Infrastructure
Download the Lync 2013 Preview VDI plugin
Citrix - http://blogs.citrix.com/2012/07/24/xendesktop-support-for-lync-2013/
VMWare - http://blogs.vmware.com/euc/2012/07/microsoft-lync-2013-support-with-vmware-view-desktops.html
Dell - http://community.wyse.com/forum/entry.php?68-Dell-Wyse-Enables-Microsoft-Lync-To-Be-Deployed-On-Its-Thin-Clients
HP - http://h20435.www2.hp.com/t5/367-Addison-Avenue-Blog/Talking-Thin-Clients-Yes-Literally-Here-s-What-HP-Has-Planned/ba-p/79021
What's great about Lync 2013’s upcoming support is the ability to choose the VDI you are working with. You aren't locked down to one virtualization or hardware vendor.
how do you think - is it possible to deploy VDI without plugin installation? I understand the limitations, but will it basically work?
Yes you can deploy without plugin but it wont be supported by Microsoft for voice and video without it. Some virtualization vendors may support voice and video without the plugin but Microsoft require it if you want to use those features.